the bullet flied so wrong, you could be something different with this same bullet, just one modification , let the email and I'll send you the scheme...
I’d be interested to see this with a tungsten carbide casing and a lead core set with a slight fin in the nose at an angle which encourages higher rotational velocity
And to expand and generalize I’d like to see a video where you alter slugs/loads you think would perform better with a minor change and compare to the originals
At super sonic speeds, there's a "shield" in front of a projectile that prevents those fins from gathering any air pressure to cause a rotation. Use those same projectiles and fit them into a sabot. Fire them out of a rifled slug barrel and I guarantee you'll see the result everyone is anticipating.
Lucky its not then how is it definitely super sonic itz heavy asf. Mayb the weight of it is too much for the puny grooves to have any effect though. But what do I know. Im only English. I learn my guns from video games and demo ranch haha.
it is more likely that the groove are intended to cause rotation from contact with the barrel. perhaps they were slightly too narrow to make proper contact.
Dear Tim: Your rounds tumbled because of shockwave propogation and boundary layer effect. When you have an object with a pointed nose travelling supersonic, the shockwave propegates all the way to the back of the object instead of going over its control surfaces. In this case, into your control channels. If you were to put this round into a supersonic wind tunnel, you'd see the shockwave propegate all the way to the rear, and no air at all going into the grooves. Effectively, they're almost working in a vacuum. All of the boundary layer air is going AROUND the bullet instead of into your grooves. A design like this COULD work, but you need to re-think your supersonic aerodynamics. First, you need an almost blunt, hemispherical nose. Think of how a missile on a jet fighter looks. They have rounded (not pointed) noses. That's so the pressure wave doesn't propegate back along the missile body and disrupt boundary layer flow over the control fins. So the nose needs to be shaped more like a missile, and less like a spear. Second, your channels need to be wider and the "fins" between them narrower. Again, you're trying to force supersonic air to go down a tube, when it really only wants to go around. There's too much static pressure buildup inside the channels for air to flow over the control surfaces and impart a lateral force to the round. Third, you need to create a wide opening for those channels at the front, tapering down to the nose tip. Think of a NACA duct. The fins should start narrowing as they start coming down the rounded nose curve. They should meet at a point in the dead center of the nose, forming a kind of star shape when seen from the front. This will smooth the transition of air into your channels, and help maintain some kind of laminar flow inside. It should also give a sort of ram-pressure effect, forcing air to pressurize at the nose, flow through the channels, impart some lateral force and exit into the drag pocket. Finally, you should consider boat-tailing the bottom-rear of the channels slightly, and tapering the control fins off to a rear-facing wedge. This will create a bit of diffusion as the high-pressure air exits, allowing it to cleanly enter the drag pocket without creating weird wake vortices and disrupting stability. This should reduce drag and net you greater range, accuracy and impact force. Hope all this helps. Looking forward to the MkII Turbine Round!
thankfully bullets do not exhibit the type of behavior you describe. most bullets even high energy penetrators with sharp noses do not exhibit shock propagation, especially not at the muzzle. it wouldn't matter anyway. non rotating bodies are inherently unstable. even if the aerodynamics worked out as intended and the groves could impart a spin downrange there would be nothing to impart a stabilizing force at the muzzle. a slug like this will tumble immediately every time unless it is some how insulated from the muzzle blast and the downrange freestream. in sabot rounds, the exit-discard interactions are extremely important to stability downrange. the sabot ring leaves the muzzle spin stabilized, then discards with no physical contact to the penetrator, which allows the penetrator to smoothly transition into aerodynamically guided flight
Andrew Sickafoose I'm not saying it would get the shockwave propagation at the muzzle. I'm assuming it would fly straight for at least a few feet...far enough to clear the muzzle blast anyway. But you're right...if it starts to tumble immediately, it wouldn't matter. I agree. I'm assuming stable flight until it gets into clean air. As far as sharp-nosed bullets not exhibiting shockwave propogation...ummm...they would if they were supersonic. They'd have to. Very least you'd lose boundary layer flow over part of the bullet's surface. That's what I'm referring to. A regular pointed bullet wouldn't have to worry about boundary layer at speed, because it already got all of its gyroscopic force in the rifled barrel. Blast effect, like you said. But a rifled slug like this would depend on surface flow at speed as much or more than blast effect. So, yeah...I think this is something that would only affect rifled slugs, and not typical bullets shot from a rifled barrel. The dynamics are different. All a bullet has to do is maintain gyroscopic spin and not fight the air too much. A rifled slug has to work with the air to maintain its stability. I'm pretty sure that would change the dynamics a little.
Richard Rowe I understand conceptually what you are saying. But a bullet is not a complex or accelerating planform or a nozzle inlet. Most bullets are not sharp compared to length and bullet with a blunt nose will always form a bow shock. Look up schlieren imagery of bullet flight. Even downrange the bow shock clearly originates near the bullet nose. Even at SS velocities there is simply not enough momentum transfer area on a shaped shotgun slug to get any kind of spin to develop in the time it would take to meaningfully stabilize the slug in the blast effect region.
Andrew Sickafoose All right, I understand what you're saying. But if that's the case, then why do rifled shotgun shells work at all? Like I said, I'm assuming it stays stable to at least a few feet out of the barrel. I'd think the blast effect inside the barrel would impart enough force to overcome initial resistance and get it spinning. At that point, I'd think you could just maintain the spin with aerodynamic forces if you got the profile right. I'll have to look at the imagery again. But yeah, I know the shockwave originates at the nose. Not sure where I said otherwise. I'm talking about how far back it stretches along the bullet surface, and at what angle. Just to be clear...I'm not advocating for this kind of design. I know it's intrinsically unstable. Or at least introducing instability where it doesn't need to be. I'm only saying that it's theoretically possible to make it work. .
Shotgun slugs are not stabilized by rotation like rifle bullets.They are stabilized by havier part in the nose like arrow.All Breneke and Foster,Gualandi and other slugs for smoothbore had plastic wad on back side to be stabilie in flight.Rifling purpose on the slug is for safe pase through any choke,even full choke.
You need a significantly higher density in the tip of the round. It would work with a rifled barrel but not the slug. Rifling on the slug requires air to go through the slits, which it won't because of the speed of the bullet. The rifled barrel will make it spin from just the slug being dragged on the rifling
You said you used a "smooth bore" , you'll need a rifled barrel if ya want this to work. Even tho the slugs have rifling you need the barrel rifling to start the rotation, the rifling on the slug's does not mean a thing if it's not rotating *before leaving the barrel.
+coal james okayy you pretty much answered the questions I had! I figured it was because the barrel wasn't starting the rotations since the inside was smooth in the shotgun. There's really no way for the slug to start rotation unless the barrel is waay long for it to stay straight to get the spiral motion. Unless a longer barrel wouldn't work?!
The slug was made so that the air friction would be channeled through the absurdly large grooves. In theory, the air pressure from the projectile moving so fast would give it the desired spin. Whether it did the job or not is another story.
In a smooth barrel, slug doesn't stabilize gyroscopically. The rifling on the slug isn't there to spin it. The grooves in the slug are so when the slug is making contact with the barrel the entire time and when it reaches the choke the led can compress into the gaps so it doesn't create a high pressure area. The way a rifled slug stabilizes is more like a pub dart. It has more weight up front pulling the rear while the rear end acts like a fin. Gyroscopic stability only applies to a smooth slug shot through a rifled barrel.
James Schaible I was thinking if they used a much longer barrel to allow the round to spin more? Or would that not matter in this case? I'm asking you cause you seem to be the most knowledgeable comment in the sea of comments on the subject lol..
James Schaible Exactly, think bad mitten birdie. The thin walled rear of a slug acts just like the feathers. So far, all they have proved is that ammunition manufacturer's know how to design ammunition. The only way to impart spin on a slug is to rifle the barrel.
seems to me that the propellant gasses would force the slug to spin the wrong way out of the barrel, then as atmospheric air forces it to spin in the opposite direction, it would become unstable
***** You hit the nail on the head bud, If they would use a sabot on the slug and get ti spinning in the right direction in the first place it would not be unstable and it would be more accurate as well.
Great video. One suggestion for the guy making these rounds: at supersonic velocities the physics of flight switch to a slight variation of fluid dynamics versus aerodynamics - which means that the projectile is now travelling in a non compressible medium. In order to maintain controlled flight there can be no "flat" surfaces towards the direction of travel. I noticed that the rounds had a small flat spot at the forward tip, if he machines them to a sharper point the rounds will likely do much better.
It's likely been mentioned before, but the charge from the shell is forcing air/gas through the grooves from behind. It's attempting to force the slug to twist in a rotation opposite that of the intended one. Whatever effect the air between the back of the barrel and the target has on the slug is being countered by the initial force from directly behind the slug. It should also be noted that, while effective for turbines, using air to rotate the projectile about the long axis of the slug is going to produce the highest rate of spin only at the very furthest end of the slug's flight. Rifling works because it forces the projectile to reach its maximum rotational velocity immediately out of the barrel, which is what stabilizes the round. The grooved slug has no such forces upon it as it is launched from a smooth bore.
This is amazing stuff, I love it. In my experience with ballistics you don't need drag to stabilize a bullet, you just need the bulk of your weight in the front. I would consider trying a tear drop design with some one in 7 fins in the back making sure that the front of the projectile is heavier than the rear by a lot. Maybe injecting lead into the front?
Great stuff! The machine work looks beautiful, I have no doubt with a little weight change, that thing will fly as straight as an arrow. Fun vid TAO, thanks for posting.
Thanks Andrew. Tim may be contacting you about another design he has made. He made 9 of them so he was hoping to send you a few to shoot at some gel. I only need 4 or so he can send the rest to you.
Just an FWY. The reason the barrel is rifled and not the bullet is because force coming from behind the bullet (propultion) Will turn it the opposite way of force stopping the bullet (wind resistance). Therefore, The bullet will likely topple through the air mid way unless there is an unknown factor.
Well said, has nobody else, (including the videomaker) considered that? Even if a plastic wad stopped the propulsion gases imparting a negative spin the grooves would have no effect while in the barrel and any spin would rely on wind resistance on exiting the barrel, then, even if you forget about supersonic shock wave issues the "fins" would be applying too little force, way too late. Once the projectile starts to tumble (because it isn't spin stabilized) those ridges would not right it. Still props to the machining and production, lovely looking slugs and they'd probably sell but poor physics/ballistics
I know why they do not work. When viewed from the rear, the initial blast hits the fins so that it spins the bullet in a CCW direction. Then, when the air grabs it from the front, it hits the fins causing it to try and rotate in the CW direction. This instantly causes it to tumble. The slots are too deep, causing too much drag, and should not go all the way from front to back. They should gradually taper off in depth to the OD.
First thing I would do, is redesign the back end. As the round exits the barrel and the gas "catches up", it could put more force on one beveled surface than the others and tumble. The grooves are what causes this, because it alters the mass symmetry. This would likely not happen on solid rounds. You also need to keep the pressure wave during flight in mind. Fire one as a sub-sonic round and see what it does. Thanks for the content!
Aerodynamically speaking those things are a nightmare. It's just one big award shape with THICK rifling, that's like putting a spoiler on a Nissan juke and calling it "aerodynamic."
You don't have enough rear pressure stop at the back of the bullet. Gas is expanding at a faster rate than the slug is traveling so it is escaping through the groves in the slug, this is causing drag on your barrel walls and over pressure at the front of your slug, that's why it tumbles when if first comes out. The rapid expansion of the gas in front of the bullet is omni-directional so there is no tip control. The reason a bullet says on target is because the pressure in front of the bullet is much lower or at ambient pressure, this allows spin to generate as air in front of the bullet tries to wrap around in inside the barrel. You are losing that to the over pressure in the front. If you used a carriage or a synthetic wad (3D thermal plastic printing could make one easily) that would generate a good enough seal if engineered right. Then they separate just like putting a satellite into orbit as they leave the muzzle... Oh and your grooves are too deep, you are going to cause turbulent flow inside those grooves. Good luck guys.
+Zach Detwiler its more simple, when the bullet is propulsed spin in one direction, an when is out the canon spin in the oposite direction, causing a unestable aerodinamic.
It's because when the explosion happens, the bullet is rotating in a direction and when it's out of the rifle the air is forcing the bullet to rotate the other way which destabilize totally the bullet (and slow it down), the rear of the bullet needs to be solid.
+Magic_Sowap Yeah totally correct. I was just reading the comments to see if anyone else touched on this fact. In order to fix it, you would need to make sure that air can't get past the bullet while its in the barrel which I don't think is possible.
+Magic_Saussage I thought the same "design flaw", but i also doubt a solid rear helps much. One would need to do something that gets the bullet rotating in the right direction already in the barrel. And then i guess the turbine is way too powerful during flight to keep up sufficient rotation, so it takes too much energy from the projectile.
LMAO! Rich people begging from the poor. 4 million views this video alone. You have plenty of money for your own unless you have some bad addiction to pay for. 7 of your viewers would do the same. Wait a sec, isnt that how most the elite get their cash hordes anyways?
How can you blame someone for not spending money on a luxury? If you want to see high quality high speed so bad then go ahead and save up for yourself.
Moon Man why arent you living in a mud hut then and you have luxury like internet and European house?. More over privileged people talking is all im hearing
+Shawn Jones I'm not living in a mud hut because I have a job that makes enough to not live in one. if you're poor it's probably your fault. Get a shower and go get an interview instead of sitting here arguing with people because they have nice things. but I know you won't because that would be harder than begging.
Anyone with a basic understanding of aerodynamics, hell, if you ever played kerbal space program, you'd know that things going super fast can't "Bite" The air very well and thus won't do what you want. They just stall.
I thought of that bullet many years ago when I was watching a sniper sharpened his bullet. I had the same idea but didn't have the tools or money to start. I hate having to watch other inventors does it before me, but the good thing about it all my idea came true. it's frustrating born as an inventor with many ideas but no tool or money to start.
When will people finally stop trying to spin a bullet from a smooth bore barrel using aerodynamics alone? It is mathematically impossible to achieve the RPM necessary without slowing down the bullet to a ridiculous degree. You don't try to apply spin to bullets fired from a smooth bore. It's unnecessary and the least efficient means for stability. You need to apply massive amounts of drag to the tail of the projectile. Also, those grooves on foster type slugs do not impart spin to the slug. They are to allow the slug to squish down through ANY choke size, so the projectile is safe in almost all guns.
interesting, but how much spin.... If the gods will it, spin it, and just go with a light material. it'd be amusingly straight flying but no impact, still would end that argument for a period of time.
My theory is that the slug is tumbling/key holing because it is made out of aluminum; it might be too light. Maybe led might stabilize more if you wee able to cast such a precise slug.
That makes no sense. In fact, since it's lighter it's easier for the air to make it spin. F = m × a. Same force but less mass = more acceleration. Actually, it would be even worse because the heavier a projectile is the more spin it needs to stabilize.
Filipe Amaral I think a heavier bullet would possibly help. If you look at the Miller twist rule: t^2=(30m)/(sd^3l(1+l^2) such that t= twist, s=gyroscopic stability factor, d=diameter of the bullet, l=bullet length and m=mass of the bullet. You can then solve for s with a given twist rate to find the gyroscopic stability of the bullet. This leads to the function s=(30m)/((t^2)(d^3)l(1+l^2) which shows the positive relationship between gyroscopic stability and mass. Note that t=T/d where T is the twist in inches per turn and l=L/d where L is the length of the bullet in inches.
Filipe Amaral True. But the aluminum would be a concern for me. Lead is easy enough to remove from a shotgun barrel but I'd be concerned with the possibility of cladding the barrel of my shotgun with aluminum. Must be a beeyotch to clean if you fire a good number of these rounds.
The reason why shotgun slugs tumble is likely linked to how it fires and the barrel it's using. And the weight and center of gravity of the slugs. You don't see this for regular rifles and bullets, because bullets themselves have the weight on the tip weighed towards the front. The slugs in this video is weighed in Aluminum throughout the whole shape, so there is no frontal center of gravity for the ammo to keep it's shape. The best modification is putting Lead on the Tip to give the front a much needed frontal weight.
I think the weight distribution in the round itself has a lot to do with tumbling. If you could some how get most of the weight forward in the round I think it would work. That's why I put the metal weight in the front of the 3D rounds.
I don't think thats the problem, i guess its the weapon since the 7.25 rounds from a m16 have the weight in the body to make the bullet bend and send shrapnel all over your insides one it hits
Monsters Payback Day The real problem is the bullet is not engaging the rifling in the barrel since it is a shotgun and has no rifling. A typical rifle uses pressures to engage the bullet and the rifling in the barrel. Putting the rifling on the bullet was a decent attempt but you are asking the system to work in reverse.
Monsters Payback Day except AR15 pattern rifles, like all rifles, have a rifled barrel to stabilize the round in the air. Most rifle bullets are bottom-heavy (because most are pointed) so all will destabilize inside a human body. 5.45x39mm used in the AK74 will tumble inside a body too. The 5.56 fragmentation comes from a thin jacket and deep cannelure, where the bullet bends and breaks. The West Germans made 7.62x51mm bullets with thin jackets and deep cannelures which made them fragment. 7.62x39mm will also tumble, it just takes more distance to do it. The reason shotgun slugs ought to be front-heavy is that from a smoothbore, rifled slugs simply can't rotate on their own - so the heavy front with a light back would keep it straight like a shuttlecock.
I think the creator did a great job and already made a great deal of progress. If I could provide any input I would suggest that this new aluminum slug actually requires a modified shotgun and shell in order to properly deliver. I propose a shell that allows a closer tolerance, within the barrel, to the bullet itself. Perhaps a metal shell? Also, the groves in the slug, ment for rifling, should uniformly withdraw to and end where they meet the metal shell at the base of the bullet thus allowing a proper seal. Such a shell should mimic that of a 5.56 or other actual rifle round (Wider at the base, withdrawing to a smaller diameter at the nose of the shell). Hopefully someone can turn this suggestion into a real masterpiece. I would love to but lack the workshop to do so.
The problem now, is the rifling goes all the way. When the powder explodes, the gases are escaping through the rifling. What then happens, is the slug leaves the barrel, and that fraction of a second is all it takes for the gases to blow it any which a way, causing it to tumble. The amount of escaping gases will also reduce the escape velocity of the slug, so it has less punch. Try gradiating the rifling, so the slug is still a whole outer diameter, at the seated end.
+TAOFLEDERMAUS Well then, it's just a crappy slug. What purpose would one that size serve? And if you need one that size, try elongating the point; you can see a marked difference between it and the .50 cal. Finally, you may be better serve by saboting a case hardened concrete nail; though you may find yourself wasting a lot of saboting materials.
Yeah, the concept just doesn't work. We made these because we've gotten SO many comments from viewers swearing it would work. You never know until you try!
Theophilus Martus Goh I think you're right. I wonder if shot over a longer range if they would correct or if he had some sort of long tube diffuser to allow the gases to escape and the slug to slide along something for that small amount of time
Look up bullet bow shockwave. These slugs are traveling at supersonic speeds causing the air at the front of the projectile to become highly compressed creating a conical waveform surrounding the slug. Basically what this means is the rifling cut in the slug doesn't actually engage the air like we imagine it would, rendering them useless. The rifling we see on foster slugs or "rifled slugs" is actually there to allow for the lead slug to be able to be compressed down through a choke and don't actually impart any spin. What gives modern slugs their stability, and therefore accuracy, is the weight forward design, and the open cavity at the base of the slug. The heavy front end keeps it from tumbling through the air like we see in the slugs from the video. The only way to get these to spin is to run them through a rifled barrel instead of a smoothbore. And if someone was willing to do that, I'd love to see how the deep rifling in these slugs transfers energy through some ballistics gel👍
Krazy Studio so there you have it. smooth barrels are for round pellets only. you gotta have a rifled barrel to spin and stabilize the projectile before it's aerodynamic spin kicks in even if the slug itself has deep rifling like that one.
with the rifling going throughout the entire bullet like that, i wonder if that has an effect on the velocity, might some gas get pushed past the bullet before it exits the barrel? cool video though
There's wadding behind the projectile preventing any gas from escaping around it, If shotgun rounds didn't have this then shot (birdshot, buckshot) would have almost no velocity.
The shockwave is preventing the wind from reaching the round so essentially it's just being slung at high speed and the rifling has no effect. Also it seems if it was to really work the round would need to be rifled from the very tip making them fragile.
***** No I'm pretty sure they're for smoothbore shotguns. You don't need a rifled slug if you have a rifled barrel but not everyone puts rifled barrels on their shotguns because you can't shoot shot out of them.
Rifled slugs are for non-rifled barrels. The "Rifling" on the slug allows it to squish down to fit through any size of shotgun choke. It is not there to spin the projectile. A projectile that short is inherently stable.
+Toozday's Child It's one of those works that no matter how I say it, someone is going to tell me I'm wrong. Tur-bine is the UK pronunciation, but a lot of Americans pronounce it that way too, but it more regional, northerner vs southerner.
Those are some well machined slugs, the looked to good to fire haha. I would like to see a similar design, however with the rifling internal. I understand this would be exponentially harder to machine.. What I mean is there would be a thin outer wall on the slug to keep a flow of air travelling through the rifling instead of being blown off by supersonic shockwaves. Kind of like a RAMJET without the combustion....
do you think that maybe the "dips" are too deep , im thinking it might make them spin too fast. they are staying on target that dont seem to be the problem, maybe make the "dips" alot more shallow and put more of them
Jorge Orozco dont listen to him...there is no ''rifled'' slug ...its just a desing in the slug so it clear all chokes...stabilisation is not acheived via rpm
hey man instead of insulting just explain to him why is he wrong. Like you cant stabilize a slug with just air.. thats why it never works... the slug just tumbles. the stabiliy comes from going to a rifled barrel giving it the rpm to continue a stable trayectory.. its middle school physics.
@rib bit subsonic that shouldn't be a problem, also supersonic if the shape is different (like a space capsule) it can be stabilised, like they also have shown on this channel. You are also not going to make a figter jet out of lead. You also have rubber and brass bullets. If you want it aerodynamically stable (so not a typical bullet), the shape (CP) and weight distribution (CG) are the most important factors. Just like a paper airplane.
@rib bit drilling a hole alone would probably not be enough either, the back end seems too slick and supersonic these flutes don't have much effect anyway
Maybe if he machines the turbine design halfway down the length of the slug and have the grooves taper upwards to cause some drift, you will have a more accurate shot/spin. From what I see, the air is going all the way down the grooves in the bullet and rather than causing a whirlwind effect, it's building a small vaccuum behind the bullet and making it wobble. Sorry if that's not worded the best, but if you get the gist of what I'm saying I'd say go for it. Cool Idea for sure.
Let me help you guys out. I know I'm a full maternity cycle late, but all you need to do is have a rifled barrel like dude said below. Also, there really is no need to make your projectile that large unless you have the thrust to make it fly straight. No need to rifle the round, unless you're hell-bent on saving projectile weight, which isn't exactly a bad thing. I would personally ramp your rifling outward to eventually become flush with the circumference of the caliber. Also, add some more kick to the round and make the projectile shorter. No more than a 1 in 7. Good luck.
+Alberto Castro The challenge is stability with OUT spin stabilization. We made this video since many people were convinced putting spiraled fluting on a projectile would impart spin. If we wanted to just take the easy-route, we'd use other peoples' designs and just rely on barrel rifling.
Sort of gives you and idea of why the early projectiles were round balls huh? People were pretty smart back in those days and most of these things have already been attempted, tested and failed years ago. Now having said all that, we should never give up on trying to improve things so I give the effort two thumbs up.
TAOFLEDERMAUS granted I have zero knowledge of supersonic aerodynamics but I have a feeling one of the big problems is that the rifling follows the entire length of the bullet so what happens is the gasses from the powder, as they expand, exert a force on the rifling as it travels the barrel and makes it spin counter clockwise instead of the slug turning clockwise as it's intended (or vice versa). you end up with the reverse effect because the gasses flow from the back of the slug up the length of the tracks until the slug leaves the end of the barrel which is when your spiral force reverses. in the short amount of time and even with a very slight amount of rotation after it leaves the barrel it wobbles for a while until the air starts flowing through the rifling the correct way but that slight wobble can cause it to start tumbling end over end. you guys should try the same kind of slugs but get someone to make the rifling tracks wider and deeper at the tip of the slug and progressively thinner and shallower as they go down in an attempt to also slightly pressurize the air that travels through the rifling tracks which should create a little more drag force on the air passing through the grooves hopefully increasing the rotation. and make it so the rifling grooves are pretty much non existent at the bottom of the slug so its just round with no visible grooves or just very tiny slits when looking at the bottom of the round, the slug should almost be the same size as the barrel (or as close as you can get) at the very back of the slug so it starts out just traveling the barrel with little to no spin at all, then gains rotation as it flies through the air.
masterof weedpuffin kinda my though also, apologies, I didn't read this till after reading down the posts. simple minds think alike...I try to stay with the K.I.S.S. method in alot of what I do in life.
+Perpetual KillMachine you need a rifled barrel, to make the bullet spin. Its the reason why you dont put birdshot in a 9mm pistol, because the rifling in the barrel spins it so it makes a large circle, not a nice neat spread
+Trevor Bilinski Shot also has a nice tendency to fuck up rifling in the barrel, that's why you get a smooth bore shotgun for shot, and a rifled shotgun for slugs.
+Aaron Clark The wad keeps shot from touching the barrel so I don't see what your talking about. The rifled barrel spins the shot and spreads it out with a big void in the center. In turn the wad spins the slug without touching the barrel. I will do some testing this spring to compare. Anybody got a spare high speed camera they can loan me.
Sabo (say-bow) projectiles have a jacket (usually plastic, that fills the void between the projectile & the inside of the bore) that makes contact with the lands and grooves of a 'rifled' barrel to cause stabilization through spin. A foster slug thru a smooth bore does not spin...the little ribs on a foster slug, are for asstetic purposes only on this nose heavy -- hollow based slug.
They tumble due to the ogival nose of the round deflecting the air flow away from the grooves so that they don’t spin stabilise. To function properly, the front ends of the groove bases would need to be tapered into an ogival shape closely paralleling the nose of the round, and the round would need to be boat-tailed to reduce drag and turbulence behind the round. The only other way would be to reduce the nose diameter to that of the groove-base’s diameter, and maybe sharpening the leading edge of each groove wall to reduce turbulence. An analogy would be the grooves on a powerboat hull that reduce friction between water and hull by deflecting water away.
I think the rounds with the spiral channels are tumbling because the the rotation imparted by by propellent escaping through the channels begins spinning the round but the spin is killed when it exits the barrel because then compressed air coming from the front spins it the other direction i.e. propellent coming from the tail will spin it clockwise but once the major pressure comes from the atmosphere, it rotates counter-clockwise. Basically, you can't have a fined projectile that picks up any spin inside the barrel from it's fins because it will spin in the opposite direction as it will in flight. None of the fletchette weapon had in barrel spinning projectiles. And artillery size fined projectiles usual are fired smooth bore with the a sabot that shields the fins from the propellent and keeps it from spinningl
Some people seem to think that the gasses projecting the slug will have some effect on the rotation or not of the projectile. This is not so because the gasses never come in contact with the projectile because of the wad between the projectile and the powder. Those who suggest that there is little ability doe sufficient air to come in contact with the grooves in the projectile are probably correct. This can be solved in several ways including expandible fins or perhaps only 4 very narrow machined fins with wide lands to allow the air to get closer to the projectile. We learn something from every experiment, if only what does NOT work.
Very interesting and cool! It appears that the grooves could be too deep. It appears that the deep grooves are acting more like air foils and are grabbing the air and creating heavy drag, which seems to be inducing an extreme amount of projectile instability.
I actually came up with a prototype yesterday for a shotgun slugs that would fly aerodynamically straight. Once I can successfully build it I will either test it out on my channel or I may submit it to y’all to test out. I never know it may not even work
Add small, spring-loaded tail fins for stability, and a titanium tip and center rod for penetration. The aluminum body will still offer light weight, while the titanium add strength for punching the target.
A solution for Tim Hamilton the problem is when the blast rushes past the projectile in the barrel the projectile spins clockwise but then the air drag reacts on the flute and reverses the direction of spin. and at zero revs the projectile end overs. Part of the solution would be to start your flute slits from the front and not complete them all the way through creating a sealed round slug at the back that prevents the blast passing the projectile also adding velocity though more efficient pressure behind the projectile. The problem with not taking material equally of the back is the projectile becomes back heavy and that end will want to travel up front. But being made out of aluminium maybe a lead or carbide nose core could shift the center of balance?
well so what I think is happening is: the slug doesn't roll inside the barrel at all, because you get pressure from the back and pressure from the front. if anything the slug would rotate in the opposite direction from expected because of the higher pressure from behind forcing it's way through the bullet's rifling - this of course could give some stability but because the air would be pushing it in the other direction after it came out of the barrel, it would serve more to distabilize it because you have the rifling working against the inertia. Even if it's not spinning at all as it comes out of the barrel, it still doesn't have any stability and it just acts like a block of aluminum. At that point if it's off even by a few degrees the rifling already doesn't work and it'll keep tumbling with no hope of stabilizing.
You have to impart a certain amount of spin to the projectile before it exists the barrel. If not, it will become a knuckleball before the machined fins can interact with the air in free space. It might also help to make the bullet "nose heavy" and create drag at the rear end like a diablo air rifle pellet.
you should try and implement the design and function of the skirt of a pellet from air rifles.. they are made to slightly expand inside the barrel when shot and seat the round to the rifling.. i believe this is how they get such low weight, low velocity rounds not to tumble and fly more effectively
***** well, disappointed i wasn't the first to mention the design but happy with seeing instant results of the theory working real world.. great videos! thanks
Looking at these I have two ideas. Firstly they are tumbling because they are not spinning enough in the length of the barrel. to speed it up I'd make the groove depth shallower, and narrow the groove from front to back. My theory being that as the bullet travels forward, the narrowing grove will force the projectile to spin quicker even after it leaves the barrel.
The problem I see with the stability is due to not enough drag on the back of the bullet. If you were to cut a taper in the thickness of the fins from the same width in the back to almost a knife blade in the front of the bullet, it may create enough drag in the back of the bullet to stabilize it by compressing the air in the groove as it gets narrower toward the back of the bullet.
The taper in the back along with the slots cut so deep all the way though help the gas's escape, which makes the bullet slow. Which is made clear by how the waddings velocity seems to try to overcome the bullet in the slow motion. Suggestion: The taper should be on the rifling and not on the bullet in total. (90 degree back into shell, Which start out round while the groves get deeper to fore).
I'm not a ballistics expert, but I would imagine a fundamental problem with "riffling" the slug is that the gas in the barrel passes through the grooves causing it to spin one direction, if it even gets spinning (would depend on the clearances i think) . as soon as it hits the still air outside of the barrel the flow direction is suddenly reversed and cause it to spin in the opposite direction. This would cause turbulence and more than likely cause the round to tumble.
contrary to popular belief, rifling on a shotgun slug is to allow the slug to compress slightly for different sized choke tubes as well as reduce surface area friction to improve velocity. You can buy rifled choke tubes to impart spin on the slug but I have no idea how that would work with an aluminum slug
I feel like what is happening is the rounds spiral is causing it to move once it leaves the barrel but the back half is still in the barrel so while the front is moving to the side the rear cannot causing the bullet to wobble. This is most likely the reason why the slugs with extended fins on the tails work decently.It would be interesting for the person who made the 3-D printed slugs to add this feature to increase the accuracy of the rounds.
If you wanted it to fly straight without rifling I'd suggest making it similar to the KE Rounds used in Tanks, the front of the nose enables are to be pushed out evenly so whilst it has high momentum the air resistance will keep it stable and impact with a point load rather than a blunt load. Id suggest the design with the jacket being a solid body part so it doesn't having a split action, therefore making it one part. Whilst this reduces max range and speed, short range accuracy should be better and should carry more mass at the expense of excessive deceleration at range.
![Megan Thee Stallion - Neva Play (feat. RM) [Official Video]](http://i.ytimg.com/vi/TpYTyAaTRts/mqdefault.jpg)
Hey! This is a really old video. Check out our SHOTGUN TRACER SLUG video for a real treat! ruclips.net/video/3H4SbfyuTes/видео.html
the bullet flied so wrong, you could be something different with this same bullet, just one modification , let the email and I'll send you the scheme...
Would they work in a musket?
This video came up in the suggestions. What a difference from today, you've made a lot of progress.
I’d be interested to see this with a tungsten carbide casing and a lead core set with a slight fin in the nose at an angle which encourages higher rotational velocity
And to expand and generalize I’d like to see a video where you alter slugs/loads you think would perform better with a minor change and compare to the originals
At super sonic speeds, there's a "shield" in front of a projectile that prevents those fins from gathering any air pressure to cause a rotation. Use those same projectiles and fit them into a sabot. Fire them out of a rifled slug barrel and I guarantee you'll see the result everyone is anticipating.
Lucky its not then how is it definitely super sonic itz heavy asf.
Mayb the weight of it is too much for the puny grooves to have any effect though.
But what do I know. Im only English. I learn my guns from video games and demo ranch haha.
it is more likely that the groove are intended to cause rotation from contact with the barrel. perhaps they were slightly too narrow to make proper contact.
.50 cal: exists
.70 cal:
*WHO'S YOUR GOD NOW*
One more god rejected
U know there are tank rounds.
@@DCW121 yes but they dont own a tank
2 bore
20 km looking at both of them like 👀
Dear Tim: Your rounds tumbled because of shockwave propogation and boundary layer effect. When you have an object with a pointed nose travelling supersonic, the shockwave propegates all the way to the back of the object instead of going over its control surfaces. In this case, into your control channels. If you were to put this round into a supersonic wind tunnel, you'd see the shockwave propegate all the way to the rear, and no air at all going into the grooves. Effectively, they're almost working in a vacuum. All of the boundary layer air is going AROUND the bullet instead of into your grooves.
A design like this COULD work, but you need to re-think your supersonic aerodynamics. First, you need an almost blunt, hemispherical nose. Think of how a missile on a jet fighter looks. They have rounded (not pointed) noses. That's so the pressure wave doesn't propegate back along the missile body and disrupt boundary layer flow over the control fins. So the nose needs to be shaped more like a missile, and less like a spear.
Second, your channels need to be wider and the "fins" between them narrower. Again, you're trying to force supersonic air to go down a tube, when it really only wants to go around. There's too much static pressure buildup inside the channels for air to flow over the control surfaces and impart a lateral force to the round.
Third, you need to create a wide opening for those channels at the front, tapering down to the nose tip. Think of a NACA duct. The fins should start narrowing as they start coming down the rounded nose curve. They should meet at a point in the dead center of the nose, forming a kind of star shape when seen from the front. This will smooth the transition of air into your channels, and help maintain some kind of laminar flow inside. It should also give a sort of ram-pressure effect, forcing air to pressurize at the nose, flow through the channels, impart some lateral force and exit into the drag pocket.
Finally, you should consider boat-tailing the bottom-rear of the channels slightly, and tapering the control fins off to a rear-facing wedge. This will create a bit of diffusion as the high-pressure air exits, allowing it to cleanly enter the drag pocket without creating weird wake vortices and disrupting stability. This should reduce drag and net you greater range, accuracy and impact force.
Hope all this helps. Looking forward to the MkII Turbine Round!
thankfully bullets do not exhibit the type of behavior you describe. most bullets even high energy penetrators with sharp noses do not exhibit shock propagation, especially not at the muzzle.
it wouldn't matter anyway. non rotating bodies are inherently unstable. even if the aerodynamics worked out as intended and the groves could impart a spin downrange there would be nothing to impart a stabilizing force at the muzzle. a slug like this will tumble immediately every time unless it is some how insulated from the muzzle blast and the downrange freestream.
in sabot rounds, the exit-discard interactions are extremely important to stability downrange. the sabot ring leaves the muzzle spin stabilized, then discards with no physical contact to the penetrator, which allows the penetrator to smoothly transition into aerodynamically guided flight
Andrew Sickafoose I'm not saying it would get the shockwave propagation at the muzzle. I'm assuming it would fly straight for at least a few feet...far enough to clear the muzzle blast anyway. But you're right...if it starts to tumble immediately, it wouldn't matter. I agree. I'm assuming stable flight until it gets into clean air.
As far as sharp-nosed bullets not exhibiting shockwave propogation...ummm...they would if they were supersonic. They'd have to. Very least you'd lose boundary layer flow over part of the bullet's surface. That's what I'm referring to. A regular pointed bullet wouldn't have to worry about boundary layer at speed, because it already got all of its gyroscopic force in the rifled barrel. Blast effect, like you said. But a rifled slug like this would depend on surface flow at speed as much or more than blast effect.
So, yeah...I think this is something that would only affect rifled slugs, and not typical bullets shot from a rifled barrel. The dynamics are different. All a bullet has to do is maintain gyroscopic spin and not fight the air too much. A rifled slug has to work with the air to maintain its stability. I'm pretty sure that would change the dynamics a little.
Richard Rowe I understand conceptually what you are saying. But a bullet is not a complex or accelerating planform or a nozzle inlet. Most bullets are not sharp compared to length and bullet with a blunt nose will always form a bow shock.
Look up schlieren imagery of bullet flight. Even downrange the bow shock clearly originates near the bullet nose.
Even at SS velocities there is simply not enough momentum transfer area on a shaped shotgun slug to get any kind of spin to develop in the time it would take to meaningfully stabilize the slug in the blast effect region.
Andrew Sickafoose All right, I understand what you're saying. But if that's the case, then why do rifled shotgun shells work at all? Like I said, I'm assuming it stays stable to at least a few feet out of the barrel. I'd think the blast effect inside the barrel would impart enough force to overcome initial resistance and get it spinning. At that point, I'd think you could just maintain the spin with aerodynamic forces if you got the profile right.
I'll have to look at the imagery again. But yeah, I know the shockwave originates at the nose. Not sure where I said otherwise. I'm talking about how far back it stretches along the bullet surface, and at what angle.
Just to be clear...I'm not advocating for this kind of design. I know it's intrinsically unstable. Or at least introducing instability where it doesn't need to be. I'm only saying that it's theoretically possible to make it work. .
Shotgun slugs are not stabilized by rotation like rifle bullets.They are stabilized by havier part in the nose like arrow.All Breneke and Foster,Gualandi and other slugs for smoothbore had plastic wad on back side to be stabilie in flight.Rifling purpose on the slug is for safe pase through any choke,even full choke.
You need a significantly higher density in the tip of the round. It would work with a rifled barrel but not the slug. Rifling on the slug requires air to go through the slits, which it won't because of the speed of the bullet. The rifled barrel will make it spin from just the slug being dragged on the rifling
You said you used a "smooth bore" , you'll need a rifled barrel if ya want this to work. Even tho the slugs have rifling you need the barrel rifling to start the rotation, the rifling on the slug's does not mean a thing if it's not rotating *before leaving the barrel.
+coal james okayy you pretty much answered the questions I had! I figured it was because the barrel wasn't starting the rotations since the inside was smooth in the shotgun. There's really no way for the slug to start rotation unless the barrel is waay long for it to stay straight to get the spiral motion. Unless a longer barrel wouldn't work?!
+Taylor Jesse just make sure the rifling in the barrel is the same rotation as the slug.
coal james obviously doesnt understand that EVERYTHING ABOUT THIS IS AERODYNAMICS BASED. The air, is your rifling.
sorry guy, you're just wrong...major manufacturers make rifled slugs and they are intended for use in smooth bore shotguns.
The slug was made so that the air friction would be channeled through the absurdly large grooves. In theory, the air pressure from the projectile moving so fast would give it the desired spin.
Whether it did the job or not is another story.
I love American innovation and creativity.
In a smooth barrel, slug doesn't stabilize gyroscopically. The rifling on the slug isn't there to spin it. The grooves in the slug are so when the slug is making contact with the barrel the entire time and when it reaches the choke the led can compress into the gaps so it doesn't create a high pressure area. The way a rifled slug stabilizes is more like a pub dart. It has more weight up front pulling the rear while the rear end acts like a fin. Gyroscopic stability only applies to a smooth slug shot through a rifled barrel.
James Schaible I was going to say the same.
James Schaible Thank you. I'm tired of explaining this one to people. Foster and Brenneke slugs work using only aerodynamic stability.
James Schaible I don't know a lot about this subject, so I found your comments very helpful.
James Schaible I was thinking if they used a much longer barrel to allow the round to spin more? Or would that not matter in this case? I'm asking you cause you seem to be the most knowledgeable comment in the sea of comments on the subject lol..
James Schaible Exactly, think bad mitten birdie. The thin walled rear of a slug acts just like the feathers. So far, all they have proved is that ammunition manufacturer's know how to design ammunition. The only way to impart spin on a slug is to rifle the barrel.
seems to me that the propellant gasses would force the slug to spin the wrong way out of the barrel, then as atmospheric air forces it to spin in the opposite direction, it would become unstable
***** It would work with a sabot, and that would also increase the muzzle energy.
***** You hit the nail on the head bud, If they would use a sabot on the slug and get ti spinning in the right direction in the first place it would not be unstable and it would be more accurate as well.
I agree with u, it's a pretty retarded design.
***** Yes, I'm surprised more people didn't realize this.
+Taylor Yarick He should have loaded it into the hull in front of a wad, then that shouldn't be a problem.
Great video. One suggestion for the guy making these rounds: at supersonic velocities the physics of flight switch to a slight variation of fluid dynamics versus aerodynamics - which means that the projectile is now travelling in a non compressible medium. In order to maintain controlled flight there can be no "flat" surfaces towards the direction of travel. I noticed that the rounds had a small flat spot at the forward tip, if he machines them to a sharper point the rounds will likely do much better.
Shoot a recoil spring out of a 12 gauge
Wow what a name....lmfao!!! Think its fap time...lol
sharpshootah88 to the fap cave
That name is brilliant
mike uffelen i thought it was to the gif cave!! Lol
suddenly beating on something while shouting where is Rachel has a very different tone to it
4:30 "sounds like a turbine, zzuiinng..."
man, that was pretty funny!
It's likely been mentioned before, but the charge from the shell is forcing air/gas through the grooves from behind. It's attempting to force the slug to twist in a rotation opposite that of the intended one. Whatever effect the air between the back of the barrel and the target has on the slug is being countered by the initial force from directly behind the slug.
It should also be noted that, while effective for turbines, using air to rotate the projectile about the long axis of the slug is going to produce the highest rate of spin only at the very furthest end of the slug's flight. Rifling works because it forces the projectile to reach its maximum rotational velocity immediately out of the barrel, which is what stabilizes the round. The grooved slug has no such forces upon it as it is launched from a smooth bore.
This is amazing stuff, I love it. In my experience with ballistics you don't need drag to stabilize a bullet, you just need the bulk of your weight in the front. I would consider trying a tear drop design with some one in 7 fins in the back making sure that the front of the projectile is heavier than the rear by a lot. Maybe injecting lead into the front?
Great stuff! The machine work looks beautiful, I have no doubt with a little weight change, that thing will fly as straight as an arrow.
Fun vid TAO, thanks for posting.
Thanks Andrew. Tim may be contacting you about another design he has made. He made 9 of them so he was hoping to send you a few to shoot at some gel. I only need 4 or so he can send the rest to you.
Sounds great. Thanks for the reference.
GY6vids If it were possible to hollow it out and pour some lead into it, I wonder if it might set the CoM far enough back to get it to fly straight.
I'd be interested to see what this could do with a hardened steel core.
GY6vids In a word... FANFUCKINTASTICALLYBADASS!! LOL!
Thank God for RUclips, this channel, and working from home. You make my day better.
I'd have made the shorter in length so a good crimp could be up on the shell to cycle in a mag fed semi shotgun
Just an FWY. The reason the barrel is rifled and not the bullet is because force coming from behind the bullet (propultion) Will turn it the opposite way of force stopping the bullet (wind resistance). Therefore, The bullet will likely topple through the air mid way unless there is an unknown factor.
tom will I posted this at 1:28 before I watch the video, alas I have been confirmed.
Well said, has nobody else, (including the videomaker) considered that? Even if a plastic wad stopped the propulsion gases imparting a negative spin the grooves would have no effect while in the barrel and any spin would rely on wind resistance on exiting the barrel, then, even if you forget about supersonic shock wave issues the "fins" would be applying too little force, way too late. Once the projectile starts to tumble (because it isn't spin stabilized) those ridges would not right it.
Still props to the machining and production, lovely looking slugs and they'd probably sell but poor physics/ballistics
I've always had a similar idea and someone finally made it. I'd never had access to the tools though since I don't have my own shop.
Cool vid! I thought they’d fly straight too! They performed nicely even though.
I know why they do not work. When viewed from the rear, the initial blast hits the fins so that it spins the bullet in a CCW direction. Then, when the air grabs it from the front, it hits the fins causing it to try and rotate in the CW direction. This instantly causes it to tumble. The slots are too deep, causing too much drag, and should not go all the way from front to back. They should gradually taper off in depth to the OD.
First thing I would do, is redesign the back end. As the round exits the barrel and the gas "catches up", it could put more force on one beveled surface than the others and tumble. The grooves are what causes this, because it alters the mass symmetry. This would likely not happen on solid rounds. You also need to keep the pressure wave during flight in mind.
Fire one as a sub-sonic round and see what it does.
Thanks for the content!
Aerodynamically speaking those things are a nightmare. It's just one big award shape with THICK rifling, that's like putting a spoiler on a Nissan juke and calling it "aerodynamic."
"SHWAAZZIIING" was my favorite part
Upon first look , it is a fantastic design. There will be changes no doubt , good luck in its future ! 😎🇦🇺👏
You don't have enough rear pressure stop at the back of the bullet. Gas is expanding at a faster rate than the slug is traveling so it is escaping through the groves in the slug, this is causing drag on your barrel walls and over pressure at the front of your slug, that's why it tumbles when if first comes out. The rapid expansion of the gas in front of the bullet is omni-directional so there is no tip control. The reason a bullet says on target is because the pressure in front of the bullet is much lower or at ambient pressure, this allows spin to generate as air in front of the bullet tries to wrap around in inside the barrel. You are losing that to the over pressure in the front. If you used a carriage or a synthetic wad (3D thermal plastic printing could make one easily) that would generate a good enough seal if engineered right. Then they separate just like putting a satellite into orbit as they leave the muzzle... Oh and your grooves are too deep, you are going to cause turbulent flow inside those grooves. Good luck guys.
+Zach Detwiler Shotgun use waddings or gas checks to keep the gases behind the projectile.
+Zach Detwiler its more simple, when the bullet is propulsed spin in one direction, an when is out the canon spin in the oposite direction, causing a unestable aerodinamic.
TAOFLEDERMAUS gotta love these online geniuses
It's because when the explosion happens, the bullet is rotating in a direction and when it's out of the rifle the air is forcing the bullet to rotate the other way which destabilize totally the bullet (and slow it down), the rear of the bullet needs to be solid.
+Magic_Sowap Glad I'm not the only one who sees the problem.
+Magic_Sowap
Yeah totally correct. I was just reading the comments to see if anyone else touched on this fact.
In order to fix it, you would need to make sure that air can't get past the bullet while its in the barrel which I don't think is possible.
+Magic_Sowap Agreed.
+Magic_Saussage I thought the same "design flaw", but i also doubt a solid rear helps much. One would need to do something that gets the bullet rotating in the right direction already in the barrel.
And then i guess the turbine is way too powerful during flight to keep up sufficient rotation, so it takes too much energy from the projectile.
+Magic_Saussage I totally no wat u sayed
Those look like fun to make. A lot of pride put into those.
Definitely SPEND the money to get better high speed cameras. It's worth it.
Can I borrow one of yours?
LMAO! Rich people begging from the poor.
4 million views this video alone. You have plenty of money for your own unless you have some bad addiction to pay for.
7 of your viewers would do the same. Wait a sec, isnt that how most the elite get their cash hordes anyways?
How can you blame someone for not spending money on a luxury? If you want to see high quality high speed so bad then go ahead and save up for yourself.
Moon Man why arent you living in a mud hut then and you have luxury like internet and European house?. More over privileged people talking is all im hearing
+Shawn Jones I'm not living in a mud hut because I have a job that makes enough to not live in one. if you're poor it's probably your fault. Get a shower and go get an interview instead of sitting here arguing with people because they have nice things. but I know you won't because that would be harder than begging.
Anyone with a basic understanding of aerodynamics, hell, if you ever played kerbal space program, you'd know that things going super fast can't "Bite" The air very well and thus won't do what you want. They just stall.
I love ksp so much lol. Stopped playing it though, since the Mac version has some kind of memory leak issue.
Isn't that why tanks' AT sabot rounds are fin stabilized? :)
That doesn't answer my question: why do they bother with adding stabilizing fins to the anti tank sabot rounds?
Alex Hurlbut
They pull the back of the sabot back to keep the tip forward.
But it won't help you glide.
Alex Hurlbut i believe it still helps as fins, just not as wings
I thought of that bullet many years ago when I was watching a sniper sharpened his bullet. I had the same idea but didn't have the tools or money to start. I hate having to watch other inventors does it before me, but the good thing about it all my idea came true. it's frustrating born as an inventor with many ideas but no tool or money to start.
When will people finally stop trying to spin a bullet from a smooth bore barrel using aerodynamics alone? It is mathematically impossible to achieve the RPM necessary without slowing down the bullet to a ridiculous degree.
You don't try to apply spin to bullets fired from a smooth bore. It's unnecessary and the least efficient means for stability. You need to apply massive amounts of drag to the tail of the projectile.
Also, those grooves on foster type slugs do not impart spin to the slug. They are to allow the slug to squish down through ANY choke size, so the projectile is safe in almost all guns.
interesting, but how much spin.... If the gods will it, spin it, and just go with a light material. it'd be amusingly straight flying but no impact, still would end that argument for a period of time.
IHCTerra uhhh an arrow spins because of the air it's flying through so...
Than why does how smooth the exterior of a supersonic jet is matter
No but if there is a Shockwave preventing the air from making contact with the grooves shouldn't it work the same
I understand how it works, but I also understand that the air doesn't actually have to make contact with the metal to be affected by its shape
My theory is that the slug is tumbling/key holing because it is made out of aluminum; it might be too light. Maybe led might stabilize more if you wee able to cast such a precise slug.
You can buy those in a store it's called a rifled slug
lol i know that. I'm just saying this exact design.
That makes no sense. In fact, since it's lighter it's easier for the air to make it spin. F = m × a. Same force but less mass = more acceleration.
Actually, it would be even worse because the heavier a projectile is the more spin it needs to stabilize.
Filipe Amaral I think a heavier bullet would possibly help. If you look at the Miller twist rule: t^2=(30m)/(sd^3l(1+l^2) such that t= twist, s=gyroscopic stability factor, d=diameter of the bullet, l=bullet length and m=mass of the bullet. You can then solve for s with a given twist rate to find the gyroscopic stability of the bullet. This leads to the function s=(30m)/((t^2)(d^3)l(1+l^2) which shows the positive relationship between gyroscopic stability and mass. Note that t=T/d where T is the twist in inches per turn and l=L/d where L is the length of the bullet in inches.
Filipe Amaral True. But the aluminum would be a concern for me. Lead is easy enough to remove from a shotgun barrel but I'd be concerned with the possibility of cladding the barrel of my shotgun with aluminum.
Must be a beeyotch to clean if you fire a good number of these rounds.
The reason why shotgun slugs tumble is likely linked to how it fires and the barrel it's using. And the weight and center of gravity of the slugs.
You don't see this for regular rifles and bullets, because bullets themselves have the weight on the tip weighed towards the front.
The slugs in this video is weighed in Aluminum throughout the whole shape, so there is no frontal center of gravity for the ammo to keep it's shape.
The best modification is putting Lead on the Tip to give the front a much needed frontal weight.
I think the weight distribution in the round itself has a lot to do with tumbling. If you could some how get most of the weight forward in the round I think it would work. That's why I put the metal weight in the front of the 3D rounds.
I don't think thats the problem, i guess its the weapon since the 7.25 rounds from a m16 have the weight in the body to make the bullet bend and send shrapnel all over your insides one it hits
Monsters Payback Day The real problem is the bullet is not engaging the rifling in the barrel since it is a shotgun and has no rifling. A typical rifle uses pressures to engage the bullet and the rifling in the barrel. Putting the rifling on the bullet was a decent attempt but you are asking the system to work in reverse.
Monsters Payback Day except AR15 pattern rifles, like all rifles, have a rifled barrel to stabilize the round in the air. Most rifle bullets are bottom-heavy (because most are pointed) so all will destabilize inside a human body. 5.45x39mm used in the AK74 will tumble inside a body too. The 5.56 fragmentation comes from a thin jacket and deep cannelure, where the bullet bends and breaks. The West Germans made 7.62x51mm bullets with thin jackets and deep cannelures which made them fragment. 7.62x39mm will also tumble, it just takes more distance to do it.
The reason shotgun slugs ought to be front-heavy is that from a smoothbore, rifled slugs simply can't rotate on their own - so the heavy front with a light back would keep it straight like a shuttlecock.
ArtisanTony WEIGHT FORWARD ...AND,ENOUGH WEIGHT.
"turban"
ITS *TURB-EYE-N
I'm gonna go get some water from the crik.
@@joshstock6591 make sure you warsh your hands while yer down there
I think the creator did a great job and already made a great deal of progress. If I could provide any input I would suggest that this new aluminum slug actually requires a modified shotgun and shell in order to properly deliver. I propose a shell that allows a closer tolerance, within the barrel, to the bullet itself. Perhaps a metal shell? Also, the groves in the slug, ment for rifling, should uniformly withdraw to and end where they meet the metal shell at the base of the bullet thus allowing a proper seal. Such a shell should mimic that of a 5.56 or other actual rifle round (Wider at the base, withdrawing to a smaller diameter at the nose of the shell). Hopefully someone can turn this suggestion into a real masterpiece. I would love to but lack the workshop to do so.
The problem now, is the rifling goes all the way. When the powder explodes, the gases are escaping through the rifling. What then happens, is the slug leaves the barrel, and that fraction of a second is all it takes for the gases to blow it any which a way, causing it to tumble. The amount of escaping gases will also reduce the escape velocity of the slug, so it has less punch.
Try gradiating the rifling, so the slug is still a whole outer diameter, at the seated end.
+Clint Carpentier There is a gas check - the wadding behind the slug the prevents the gases from blowing past the slug.
+TAOFLEDERMAUS
Well then, it's just a crappy slug. What purpose would one that size serve? And if you need one that size, try elongating the point; you can see a marked difference between it and the .50 cal. Finally, you may be better serve by saboting a case hardened concrete nail; though you may find yourself wasting a lot of saboting materials.
Yeah, the concept just doesn't work. We made these because we've gotten SO many comments from viewers swearing it would work. You never know until you try!
your right! he can make the base of the slug with no rifling, to help in taking the power of expanded gases
The wadding in the shotgun shell seals the gases.
I wonder if you could make these out of rabbit poop?
Always one party pooper.
didnt mean to. i went to do yourssss
TheXtraMan why the fuck not! it lets more people see it.
Very Cool stuff Guy's! I find myself playing Catch-Up; But that just gv's Me more to look forward to! Thanks for Sharing,And B Safe Guy's!
✌✌✌
I think the problem is that the slugs are not exiting the shoty straight.
Theophilus Martus Goh I think you're right. I wonder if shot over a longer range if they would correct or if he had some sort of long tube diffuser to allow the gases to escape and the slug to slide along something for that small amount of time
Look up bullet bow shockwave. These slugs are traveling at supersonic speeds causing the air at the front of the projectile to become highly compressed creating a conical waveform surrounding the slug. Basically what this means is the rifling cut in the slug doesn't actually engage the air like we imagine it would, rendering them useless. The rifling we see on foster slugs or "rifled slugs" is actually there to allow for the lead slug to be able to be compressed down through a choke and don't actually impart any spin. What gives modern slugs their stability, and therefore accuracy, is the weight forward design, and the open cavity at the base of the slug. The heavy front end keeps it from tumbling through the air like we see in the slugs from the video. The only way to get these to spin is to run them through a rifled barrel instead of a smoothbore. And if someone was willing to do that, I'd love to see how the deep rifling in these slugs transfers energy through some ballistics gel👍
+Theophilus Martus Goh does the shotgun barrel even have rifling? that's the critical factor here.
They used a smoothbore barrel (no rifling) that's most likely why the weren't spinning well enough
Krazy Studio so there you have it. smooth barrels are for round pellets only. you gotta have a rifled barrel to spin and stabilize the projectile before it's aerodynamic spin kicks in even if the slug itself has deep rifling like that one.
with the rifling going throughout the entire bullet like that, i wonder if that has an effect on the velocity, might some gas get pushed past the bullet before it exits the barrel? cool video though
Adrian Teply I don't think so. I believe the round usually has a sabot or wadding that would prevent that.
There's wadding behind the projectile preventing any gas from escaping around it, If shotgun rounds didn't have this then shot (birdshot, buckshot) would have almost no velocity.
The shockwave is preventing the wind from reaching the round so essentially it's just being slung at high speed and the rifling has no effect.
Also it seems if it was to really work the round would need to be rifled from the very tip making them fragile.
just a thought.. maybe if the shells were half the size the tumbling factor might be eliminated..
+Logan Scott hey look at that someone else who knows physics. I agree, the round would be less effected by the air around it
I wonder if a different material (¿lead?) would have made a difference?
Ehem, I, uh, also wonder if they were rifling your barrel...
I think a carbide tip would add some fun. 😃 Thank you for all of your videos. I really enjoy watching the ballistics of the different rounds.
aren't rifled slugs intended to be used in rifled barrels to make them spin?
***** No I'm pretty sure they're for smoothbore shotguns. You don't need a rifled slug if you have a rifled barrel but not everyone puts rifled barrels on their shotguns because you can't shoot shot out of them.
no, slugs without rifling are meant to be used in rifled barrels, as are sabots
ha, okay :) thanks
Rifled slugs are for non-rifled barrels. The "Rifling" on the slug allows it to squish down to fit through any size of shotgun choke. It is not there to spin the projectile. A projectile that short is inherently stable.
Tombs Clawtooth this
Oh my god, turBINE. Rhymes with MINE. Turbans are headwraps.
+Toozday's Child I'm surprised how many people don't look up pronunciations of words before they claim someone is wrong.
***** I'm surprised how many commonly used pronunciations are fragrantly wrong. Funny how that works out.
+Toozday's Child Let me google that for you: www.merriam-webster.com/dictionary/turbine
+Toozday's Child It's one of those works that no matter how I say it, someone is going to tell me I'm wrong. Tur-bine is the UK pronunciation, but a lot of Americans pronounce it that way too, but it more regional, northerner vs southerner.
They say things like that here in Hampton roads. Portsmouth is pronounced ports muth, Norfolk is pronounced nor fuck, etc. not a huge deal.
This slug is like the minie reborn, and with a vengeance!
Those are the scariest hands ive ever seen.
ok
Needs to moisturize.
Irrelevant
I thought you said you have some 'turban' rounds...
TheJohnDenim lol
Those are some well machined slugs, the looked to good to fire haha.
I would like to see a similar design, however with the rifling internal. I understand this would be exponentially harder to machine..
What I mean is there would be a thin outer wall on the slug to keep a flow of air travelling through the rifling instead of being blown off by supersonic shockwaves.
Kind of like a RAMJET without the combustion....
+Nick Morgan Actually more like a SCRAMJET minus the combustion...
do you think that maybe the "dips" are too deep , im thinking it might make them spin too fast. they are staying on target that dont seem to be the problem, maybe make the "dips" alot more shallow and put more of them
Сначала пороховые газы в стволе раскручивают пулю в одну сторону, а потом воздух в другую. В итоге получается херня.
Просто болванка,но опасная для живых существ на некотором расстоянии.
Если пыж нормальный добавить, должно помочь по идее или подкалиберной сделать в корпусе, как та-же пуля Полева
Кусок говна . Кувыркается как хочет
Old video but wow I had high hopes for this one. Love your videos
Isnt rifling done into the barrel?? Not the bullet...
Jorge Orozco A lot of shotguns are smooth bore so they need rfled slugs. They do have rifled barrels too.
Jorge Orozco dont listen to him...there is no ''rifled'' slug ...its just a desing in the slug so it clear all chokes...stabilisation is not acheived via rpm
Ragimund VonWallat quick google search will say other wise. Plus I have a ton of 20ga rifled slugs around so, you were saying?
hey man instead of insulting just explain to him why is he wrong. Like you cant stabilize a slug with just air.. thats why it never works... the slug just tumbles. the stabiliy comes from going to a rifled barrel giving it the rpm to continue a stable trayectory.. its middle school physics.
sorry for the grammar, english not my first language..
U need to drill a hole in the back to make it front heavy. Design these as if they are darts
@rib bit subsonic that shouldn't be a problem, also supersonic if the shape is different (like a space capsule) it can be stabilised, like they also have shown on this channel. You are also not going to make a figter jet out of lead. You also have rubber and brass bullets. If you want it aerodynamically stable (so not a typical bullet), the shape (CP) and weight distribution (CG) are the most important factors. Just like a paper airplane.
@rib bit drilling a hole alone would probably not be enough either, the back end seems too slick and supersonic these flutes don't have much effect anyway
@rib bit it's all speculation though before tested
@rib bit yikes, never knew anyone was trying to kill with rubber lol
Aluminium also yields much easier than brass and fouls
Maybe if he machines the turbine design halfway down the length of the slug and have the grooves taper upwards to cause some drift, you will have a more accurate shot/spin. From what I see, the air is going all the way down the grooves in the bullet and rather than causing a whirlwind effect, it's building a small vaccuum behind the bullet and making it wobble. Sorry if that's not worded the best, but if you get the gist of what I'm saying I'd say go for it. Cool Idea for sure.
why no ballistic gel? is it expensive?
Albert Diones i think its boring after awhile
?Man, if you could increase the accuracy that would be a devastating round. It obliterated that HDD
Let me help you guys out. I know I'm a full maternity cycle late, but all you need to do is have a rifled barrel like dude said below. Also, there really is no need to make your projectile that large unless you have the thrust to make it fly straight. No need to rifle the round, unless you're hell-bent on saving projectile weight, which isn't exactly a bad thing. I would personally ramp your rifling outward to eventually become flush with the circumference of the caliber. Also, add some more kick to the round and make the projectile shorter. No more than a 1 in 7. Good luck.
+Alberto Castro The challenge is stability with OUT spin stabilization. We made this video since many people were convinced putting spiraled fluting on a projectile would impart spin. If we wanted to just take the easy-route, we'd use other peoples' designs and just rely on barrel rifling.
I see. Well in that respect, I believe you made your point.
Were those Hillary Clinton's hard drives?
They were Bleach bit
Loooooooool! =]]]]]
Oh no you haven’t “committed suicide” for this comment in the past five years have you?
@@skibooski6884 I sure hope not
Shot #1 2:10
Shot #2 2:25
Shot #3 2:44
Shot #4 2:57
Sort of gives you and idea of why the early projectiles were round balls huh? People were pretty smart back in those days and most of these things have already been attempted, tested and failed years ago. Now having said all that, we should never give up on trying to improve things so I give the effort two thumbs up.
seemed like a lack of effort on creating targets. probably took a long while to make those slugs. you shot the first pieces of trash you could find.
wah
TAOFLEDERMAUS granted I have zero knowledge of supersonic aerodynamics but I have a feeling one of the big problems is that the rifling follows the entire length of the bullet so what happens is the gasses from the powder, as they expand, exert a force on the rifling as it travels the barrel and makes it spin counter clockwise instead of the slug turning clockwise as it's intended (or vice versa). you end up with the reverse effect because the gasses flow from the back of the slug up the length of the tracks until the slug leaves the end of the barrel which is when your spiral force reverses. in the short amount of time and even with a very slight amount of rotation after it leaves the barrel it wobbles for a while until the air starts flowing through the rifling the correct way but that slight wobble can cause it to start tumbling end over end. you guys should try the same kind of slugs but get someone to make the rifling tracks wider and deeper at the tip of the slug and progressively thinner and shallower as they go down in an attempt to also slightly pressurize the air that travels through the rifling tracks which should create a little more drag force on the air passing through the grooves hopefully increasing the rotation. and make it so the rifling grooves are pretty much non existent at the bottom of the slug so its just round with no visible grooves or just very tiny slits when looking at the bottom of the round, the slug should almost be the same size as the barrel (or as close as you can get) at the very back of the slug so it starts out just traveling the barrel with little to no spin at all, then gains rotation as it flies through the air.
masterof weedpuffin kinda my though also, apologies, I didn't read this till after reading down the posts. simple minds think alike...I try to stay with the K.I.S.S. method in alot of what I do in life.
masterof weedpuffin I think the channels can be much much narrower and maybe just 3 or 5 of them.
What do you want them to shoot at? Gold coated targets with diamond studs?
it's not the rounds fault it's the guns fault
how so? a bent arrow is not a bows fault... the gun fits its usual application well, maybe its the engineers fault.
+Perpetual KillMachine you need a rifled barrel, to make the bullet spin. Its the reason why you dont put birdshot in a 9mm pistol, because the rifling in the barrel spins it so it makes a large circle, not a nice neat spread
+Trevor Bilinski Shot also has a nice tendency to fuck up rifling in the barrel, that's why you get a smooth bore shotgun for shot, and a rifled shotgun for slugs.
+Aaron Clark that would make a lot of sense, small metal spheres that go supersonic(potentially) hit grooves and would damage it
+Aaron Clark The wad keeps shot from touching the barrel so I don't see what your talking about. The rifled barrel spins the shot and spreads it out with a big void in the center. In turn the wad spins the slug without touching the barrel. I will do some testing this spring to compare. Anybody got a spare high speed camera they can loan me.
Sabo (say-bow) projectiles have a jacket (usually plastic, that fills the void between the projectile & the inside of the bore) that makes contact with the lands and grooves of a 'rifled' barrel to cause stabilization through spin. A foster slug thru a smooth bore does not spin...the little ribs on a foster slug, are for asstetic purposes only on this nose heavy -- hollow based slug.
aluminium is just not heavy enough
steel or lead core.
Another cool vid Taofledermaus! Thanks!
The problem is that you are using aluminum and not aluminium.
you get hella views so get better high speed cams
I'll try to shit one out just for you.
OK vetem
OK veterani
OK vetem
OK
the 1/20 twist seems to be the most powerful. epic rounds xD
Are those Hillary's hard drives? 🤣
Its turbine not turban
yeah, I said turbine
TAOFLEDERMAUS no you said turban
Vitor Fogaco turbine may be pronounced as turban
They fly out of the barrel going "ALAHALAHALALALALALALA" *BOOM*
c'mon we all were thinking it
He said turbin like tur + bin as in a recycling "bin". It's tur-BINE. Bine rimes with "pine" as in a pine tree.
Your passion for destruction is phenomenal. I hope you will get one of those back at ya.
+Temerator1 I don't know what you are implying.
+TAOFLEDERMAUS
“Father, forgive them, for they do not know what they are doing"
I don't know why but youtube has been recommending this 6 years old video to me for months now.
They tumble due to the ogival nose of the round deflecting the air flow away from the grooves so that they don’t spin stabilise. To function properly, the front ends of the groove bases would need to be tapered into an ogival shape closely paralleling the nose of the round, and the round would need to be boat-tailed to reduce drag and turbulence behind the round. The only other way would be to reduce the nose diameter to that of the groove-base’s diameter, and maybe sharpening the leading edge of each groove wall to reduce turbulence. An analogy would be the grooves on a powerboat hull that reduce friction between water and hull by deflecting water away.
I think the rounds with the spiral channels are tumbling because the the rotation imparted by by propellent escaping through the channels begins spinning the round but the spin is killed when it exits the barrel because then compressed air coming from the front spins it the other direction i.e. propellent coming from the tail will spin it clockwise but once the major pressure comes from the atmosphere, it rotates counter-clockwise.
Basically, you can't have a fined projectile that picks up any spin inside the barrel from it's fins because it will spin in the opposite direction as it will in flight. None of the fletchette weapon had in barrel spinning projectiles. And artillery size fined projectiles usual are fired smooth bore with the a sabot that shields the fins from the propellent and keeps it from spinningl
Some people seem to think that the gasses projecting the slug will have some effect on the rotation or not of the projectile. This is not so because the gasses never come in contact with the projectile because of the wad between the projectile and the powder. Those who suggest that there is little ability doe sufficient air to come in contact with the grooves in the projectile are probably correct. This can be solved in several ways including expandible fins or perhaps only 4 very narrow machined fins with wide lands to allow the air to get closer to the projectile. We learn something from every experiment, if only what does NOT work.
Very interesting and cool! It appears that the grooves could be too deep. It appears that the deep grooves are acting more like air foils and are grabbing the air and creating heavy drag, which seems to be inducing an extreme amount of projectile instability.
I actually came up with a prototype yesterday for a shotgun slugs that would fly aerodynamically straight. Once I can successfully build it I will either test it out on my channel or I may submit it to y’all to test out. I never know it may not even work
Add small, spring-loaded tail fins for stability, and a titanium tip and center rod for penetration. The aluminum body will still offer light weight, while the titanium add strength for punching the target.
I like to thank you gentlemen, I really enjoy watching your video especially the high speed slow motion shots..... awesome.
A solution for Tim Hamilton
the problem is when the blast rushes past the projectile in the barrel
the projectile spins clockwise
but then the air drag reacts on the flute and reverses the direction of spin.
and at zero revs the projectile end overs.
Part of the solution would be to start your flute slits from the front and not complete them all the way through
creating a sealed round slug at the back that prevents the blast passing the projectile
also adding velocity though more efficient pressure behind the projectile.
The problem with not taking material equally of the back is the projectile becomes back heavy and that end will want to travel up front.
But being made out of aluminium maybe a lead or carbide nose core could shift the center of balance?
There is a gas piston sealing the gases behind the slug
Awesome informational educational video experience Y'alls God Bless Ya 🙏
Sure looks like it'd work. Possibly the material vs weight could make all the difference here along with the right twist ratio.
well so what I think is happening is: the slug doesn't roll inside the barrel at all, because you get pressure from the back and pressure from the front. if anything the slug would rotate in the opposite direction from expected because of the higher pressure from behind forcing it's way through the bullet's rifling - this of course could give some stability but because the air would be pushing it in the other direction after it came out of the barrel, it would serve more to distabilize it because you have the rifling working against the inertia. Even if it's not spinning at all as it comes out of the barrel, it still doesn't have any stability and it just acts like a block of aluminum. At that point if it's off even by a few degrees the rifling already doesn't work and it'll keep tumbling with no hope of stabilizing.
You have to impart a certain amount of spin to the projectile before it exists the barrel. If not, it will become a knuckleball before the machined fins can interact with the air in free space. It might also help to make the bullet "nose heavy" and create drag at the rear end like a diablo air rifle pellet.
We need Evan Perry to make one of these!
you should try and implement the design and function of the skirt of a pellet from air rifles.. they are made to slightly expand inside the barrel when shot and seat the round to the rifling.. i believe this is how they get such low weight, low velocity rounds not to tumble and fly more effectively
+Dutch Boss we just did that in this video. Are you right? let's find out!
ruclips.net/video/AlIDQCgZoUc/видео.html
*****
well, disappointed i wasn't the first to mention the design but happy with seeing instant results of the theory working real world.. great videos! thanks
Crazy video guys!! Just a small note, music credits are for Ethan Meixsell, not Nathan Meixswell. Cheers
Looking at these I have two ideas. Firstly they are tumbling because they are not spinning enough in the length of the barrel. to speed it up I'd make the groove depth shallower, and narrow the groove from front to back. My theory being that as the bullet travels forward, the narrowing grove will force the projectile to spin quicker even after it leaves the barrel.
The problem I see with the stability is due to not enough drag on the back of the bullet. If you were to cut a taper in the thickness of the fins from the same width in the back to almost a knife blade in the front of the bullet, it may create enough drag in the back of the bullet to stabilize it by compressing the air in the groove as it gets narrower toward the back of the bullet.
The taper in the back along with the slots cut so deep all the way though help the gas's escape, which makes the bullet slow. Which is made clear by how the waddings velocity seems to try to overcome the bullet in the slow motion. Suggestion: The taper should be on the rifling and not on the bullet in total. (90 degree back into shell, Which start out round while the groves get deeper to fore).
I'm not a ballistics expert, but I would imagine a fundamental problem with "riffling" the slug is that the gas in the barrel passes through the grooves causing it to spin one direction, if it even gets spinning (would depend on the clearances i think) . as soon as it hits the still air outside of the barrel the flow direction is suddenly reversed and cause it to spin in the opposite direction. This would cause turbulence and more than likely cause the round to tumble.
contrary to popular belief, rifling on a shotgun slug is to allow the slug to compress slightly for different sized choke tubes as well as reduce surface area friction to improve velocity. You can buy rifled choke tubes to impart spin on the slug but I have no idea how that would work with an aluminum slug
Darrens laugh cracks me up. Reminds me of a cartoon characters laugh.
Looks like one of those pens with all the colors.
I feel like what is happening is the rounds spiral is causing it to move once it leaves the barrel but the back half is still in the barrel so while the front is moving to the side the rear cannot causing the bullet to wobble. This is most likely the reason why the slugs with extended fins on the tails work decently.It would be interesting for the person who made the 3-D printed slugs to add this feature to increase the accuracy of the rounds.
If you wanted it to fly straight without rifling I'd suggest making it similar to the KE Rounds used in Tanks, the front of the nose enables are to be pushed out evenly so whilst it has high momentum the air resistance will keep it stable and impact with a point load rather than a blunt load.
Id suggest the design with the jacket being a solid body part so it doesn't having a split action, therefore making it one part. Whilst this reduces max range and speed, short range accuracy should be better and should carry more mass at the expense of excessive deceleration at range.