Also, increased spiral on a projectile will increase accurate but decreases range. I'm an archer and when I was tuning my arrows I was going between two fletchings one had more spin the other had less. I preferred the lower spin for the higher velocity arrow. But I'm sure that you knew this my good sniper sir.
I would also add (two years late unfortunately) that since this is nerf, predictability outweighs range in most situations. If you familiarize yourself with the flight trajectory of the darts with a blaster with a SCAR barrel, you can indeed become a "nerf sniper." However you raise a valid point with the decrease range which is what you intended to do so you are correct.
In actual ballistics there is a formula for ideal rifling. I'm not sure if it is dependant on velocity or specified range or grains but some of that may apply here.
After a certain point the twist rate will make full length darts rear stick out and mess up shots so in some cases, slower twist rate can be a bit better, also less fps reduction
PhilTaylorPhotog was on the right track, as I'm quite sure that with shooting rifles the frequency of the sine curve, (by that I'm refering to the harshness of the curve of the rifling) directly relates to the speed (fps) of the projectile. I think the weight length and diameter also come into play when determining how many rotations per unit of distance the projectile needs to maintain stability.
Thanks for doing the video so fast. I assume a 3D printed rifled barrel would not have the smoothness hence even tho it does turn the dart it wont be very efficent compared the the scar.
I believe it would depend on the spring load as Bradley Phillips has explained in another comment. Would also depend on the dart and other factors. It comes down to testing. I spent 4 hours today testing and I like where I'm at so far in terms of accuracy and range.
I would argue that the overall physics of spinning darts is still very much an un known subject. Little is known on the formula for amount of spin to the amount of ‘accuracy’.
What dart size was that with and what blaster? as using the Donald Miller rule you can calculate the stability of a plastic headed projectiles (though this is designed for real steel firearms) with a given barrel twist arxiv.org/ftp/arxiv/papers/1410/1410.5340.pdf reworking the equation you can calculate the necessary twist to provide stable accuracy, plugging in the numbers for a nerf dart at 2.7" and assuming a 200fps velocity both barrels are inadequate needing a ~1:1.1 twist however using cut down 1" darts the twist ration should be between 1:4.38 and 1:5.23. Given both barrels are ~2.5" using cut down prototype darts you would be getting the perfect twist with the rifled barrel the SCAR would still be in the optimum section but closer to the stable but less accurate side of the spectrum, cut down elites to 1" however with their slightly different rotation would be inadequate in the rifled barrel though optimized in the SCAR. Given what you've said there's probably more going on than just spin being imparted on the darts, if I'm honest I'm a bit skeptical on the whole providing spin to darts increases accuracy, though I do think it would be interesting to construct a whole bunch of SCAR or rifled barrels at equal lengths with different twists including a control with no twist at all just straight and see the results.
The correlation may be true but that does not imply causation of accuracy. The SCAR barrel also has porting holes where the air from the barrel can leak out, causing reduction of backblast; the rifled barrel does not have these holes to allow backblast to vent. I would hypothesise it is a combination of the centering of the dart by the rifling combined with the venting of the backblast through the barrel's porting that permits the blasters firing from these barrels to be more accurate.
That is possible. I'd actually speculate that there would be less velocity drop off due to lower friction between the barrel and the dart, since the rifled edges are fixed, not a deforming contact point like the strings in a SCAR. Try drilling some holes at each quadrant of the rifling where it starts and see if that changes anything.
Can agree with that one. I'm currently jumping between SCARs for testing purposes on my various blasters, still finding individual sweet spots and I'm enjoying the science. I'd recommend SCARs over rifled barrels any day. Nylon string is way more durable than thin PLA/ABS grooves.
Also, increased spiral on a projectile will increase accurate but decreases range. I'm an archer and when I was tuning my arrows I was going between two fletchings one had more spin the other had less. I preferred the lower spin for the higher velocity arrow.
But I'm sure that you knew this my good sniper sir.
I would also add (two years late unfortunately) that since this is nerf, predictability outweighs range in most situations. If you familiarize yourself with the flight trajectory of the darts with a blaster with a SCAR barrel, you can indeed become a "nerf sniper." However you raise a valid point with the decrease range which is what you intended to do so you are correct.
Awesome! You should test their effect on fps.
In actual ballistics there is a formula for ideal rifling. I'm not sure if it is dependant on velocity or specified range or grains but some of that may apply here.
After a certain point the twist rate will make full length darts rear stick out and mess up shots so in some cases, slower twist rate can be a bit better, also less fps reduction
PhilTaylorPhotog was on the right track, as I'm quite sure that with shooting rifles the frequency of the sine curve, (by that I'm refering to the harshness of the curve of the rifling) directly relates to the speed (fps) of the projectile. I think the weight length and diameter also come into play when determining how many rotations per unit of distance the projectile needs to maintain stability.
Thanks for doing the video so fast. I assume a 3D printed rifled barrel would not have the smoothness hence even tho it does turn the dart it wont be very efficent compared the the scar.
I'm putting a rifled barrel on my dart zone nexus pro, I'm gonna see how accurate it is.
I thought they were pretty much the same. I ha e a Zakaro SCAR barrel which is just like the riffled barrel you showed.
Will you doing a test on amount of fps drops btw scar and rifled barrel?
Bradley Phillips oh...thanks mate
Ok but who is printing these rifled barrels??
Why not half lengts
Was the rifled barrel 9/16? And/or was it shorter than the scar?
Ollie wtf you doing here
Approx same bore size as your monochrome one?
But what's better? Faster or slower spinning?
I believe it would depend on the spring load as Bradley Phillips has explained in another comment. Would also depend on the dart and other factors. It comes down to testing. I spent 4 hours today testing and I like where I'm at so far in terms of accuracy and range.
Does one decrease FPS more than the other though?
That- Mann, never really tested fps differences because accuracy is way more important to me. I will test when I have a Jet ZRO though.
Bradley Phillips that was a FAST reply. Do you have a patreon or some way I can help you buy a chrono?
I actually have a chrono these days :)
Bradley Phillips Great! I'm still waiting to get mine until I have an etsy set up to sell some blasters.
I would argue that the overall physics of spinning darts is still very much an un known subject. Little is known on the formula for amount of spin to the amount of ‘accuracy’.
What dart size was that with and what blaster? as using the Donald Miller rule you can calculate the stability of a plastic headed projectiles (though this is designed for real steel firearms) with a given barrel twist arxiv.org/ftp/arxiv/papers/1410/1410.5340.pdf reworking the equation you can calculate the necessary twist to provide stable accuracy, plugging in the numbers for a nerf dart at 2.7" and assuming a 200fps velocity both barrels are inadequate needing a ~1:1.1 twist however using cut down 1" darts the twist ration should be between 1:4.38 and 1:5.23. Given both barrels are ~2.5" using cut down prototype darts you would be getting the perfect twist with the rifled barrel the SCAR would still be in the optimum section but closer to the stable but less accurate side of the spectrum, cut down elites to 1" however with their slightly different rotation would be inadequate in the rifled barrel though optimized in the SCAR. Given what you've said there's probably more going on than just spin being imparted on the darts, if I'm honest I'm a bit skeptical on the whole providing spin to darts increases accuracy, though I do think it would be interesting to construct a whole bunch of SCAR or rifled barrels at equal lengths with different twists including a control with no twist at all just straight and see the results.
The correlation may be true but that does not imply causation of accuracy. The SCAR barrel also has porting holes where the air from the barrel can leak out, causing reduction of backblast; the rifled barrel does not have these holes to allow backblast to vent. I would hypothesise it is a combination of the centering of the dart by the rifling combined with the venting of the backblast through the barrel's porting that permits the blasters firing from these barrels to be more accurate.
That is possible. I'd actually speculate that there would be less velocity drop off due to lower friction between the barrel and the dart, since the rifled edges are fixed, not a deforming contact point like the strings in a SCAR. Try drilling some holes at each quadrant of the rifling where it starts and see if that changes anything.
Can agree with that one. I'm currently jumping between SCARs for testing purposes on my various blasters, still finding individual sweet spots and I'm enjoying the science. I'd recommend SCARs over rifled barrels any day. Nylon string is way more durable than thin PLA/ABS grooves.
The physics is there. Any inconsistency on the dart that causes it to veer off in flight will be equalized as it is spun.
what sorcery is this?! just kidding. good video
first baby