The lighter valve spring worked an absolute treat on my CP2. I also put in a stronger hammer spring and made the action horrible. Harder to cock. Harder to adjust the trigger to something relatively safe. I bought a Crossmsn Ratcather valve spring for about £3 and it was absolutely spot on.
The pressure inside the valve will always be equal to the pressure inside the co2 cartridge. Increasing the volume inside the valve will give you more co2 to push the pellet out of the barrel.
Yes,... I've taken a lot of shit from people about doing this but it's very simple,... The time that the valve is open from the hammer striking it is what determines how much air is behind the pellet,... The pressure is what the CO2 cartridge has & no more,... I simply wanted to supply enough air for the time that the valve is open, any extra will just stay in the cylinder after the valve closes. Porting is something else,... I actually lowered velocity on my .177 version because I opened the ports to the same size as this .22 & I ruined it because it's actually lower in power now due to less pressure,... The .22 is great because the heavier pellet holds back to build pressure before it starts moving.
Too bad it's still not true, yes psi will even out. But with the same hammer and valve you've done absolutely nothing but voided warranty. If you want a stronger gun convert it to hpa or buy a real pcp. You get shit because it harms your performance not helps it.
@@matthew33721 Dude, loading the hammer simply smacks the valve stem harder,.... You still have the same load on the return spring during opening AND closing of the valve,... The hammer smacking the valve stem and the back of the air chamber harder simply smacks it harder,... Smacking it harder simply increases force on those parts
Hallo David, habe heute einen ORing eingebaut. Alles hat super funktioniert. Ich danke Dir nochmals für deine sachkundige Hilfe. Grüße aus Deutschland von Harald
The reasoning on gas pressure is not correct for CO2. This is because inside the capsule there is no CO2-gas but CO2 liquid with only a small portion of CO2 gas under a pressure of 56 to 60 bar at room temperature. The moment the capsule gets pierced, the gas will fill the gas chamber and because the liquid will evaporate to fill up the extra room, the pressure will not drop. Up to the point that all liquid is evaporated, the pressure will stay almost the same. However, during evaporation (which cost energy) the chamber will cool down, and you should therefore avoid rapidly shooting as cooling will lower the pressure of the gas. Shooting in 30 to 60 seconds intervals should avoid to much cooling down.
I've modded these in the past increasing the volume inside the valve increases the muzzle volocity sometimes it can be almost 3ftlbs increase as well as opening the valve port to 4mm as well as the tp and barrel I had a .177 cp2 when they first came out made this mod it went from shooting at 7ftlbs to 11.2ftlbs
Increasing the chambers volume will not give you a performance upgrade. Actually the opposite. I'd like to see your fps before and after because it does absolutely nothing for your performance
@matthewtunstill3372 reading your reply. This. Jay & I'm asking. Would it lower your. Fps. ??? If you hollow out the chambers valves & cut threads in half. creating more or. Larger volume of compressed air ???
@matthewtunstill3372 on my 1322. I cut 3 threads off. Creating. A slight bit more air volume space. , it went from 10 pumps at. 468. To 15 pumps to get same pressure & shot. at. 486. , then installed new 14.6 in barrel. , slightly. Barely. Drilled. Exhaust port , mabey 1. mm larger & then some trigger adjusting to about. 1.3 lbs & then shot at. 613 612. 607. 609 610. 615. & that's as far as I'm going for now anyway, I'd like to see. 700. But that's a short ways off I think. If possible , but your thoughts. If. ya don't mind. ???....
Your thinking right you can also trim that pop it down to increase a little more to increase space in the valve it only needs enough to hold the spring on the tip .💯🎯🛠️😉
It might be true that increasing valve volume increases performance. The reason is simple. Co2 from the capsule has to go in the valve through small tiny puncture pin. During a shot action it has probably no time to go to the system. Increasing valve opening time ads some more gas to the barrel but it is not the gas from capsule. Indeed it looks like decreasing small spring tension is the way to go rather then beefing up the bigger one.
You will find more info on the generic "CP2" but most of the mods are to increase power not improve efficiency. Being a retired physicist-engineer the first thing I did was strip my CP2 down and examine it. Oh dear. Decent parts but poor fit and finish at the factory. The hammer /must/ slide smoothly so it delivers the same force each time. Burrs in the 'action tube' should not be there. polish them out with a long home-made flap sander. The rifling had a few burrs too, the long wire barrel brush. That alone should make the airgun more efficient, greater fps, less spread, more shots per cylinder. The factory lubricants are poor, use quality oils and greases. Beware the tiny little screw that holds the breech to the action tube, it's what I call a bad engineering solution, it is not man for the job: do not force it tight. Hold breech block to the action tube (compress the transfer port) and nip the little screw up with the short end on the Allen. The CO2 gas pressure holds the exhaust valve shut. The valve spring does practically nothing except keep the poppet in place when there is no gas pressure. With it on the bench you can open the valve with your finger. When it is full the vapour pressure of the liquid CO2 will exert nominal 850psi (it varies with temperature). The CO2 can self-regulate. The valve is a balancer between the pressure in the valve and the constant impact force of the hammer, the less pressure in the valve, the longer the hammer will open the valve, &vv. If you increase the power of the spring the hammer just releases all of the gas, there is no regulation, and hence wild grouping and an empty cylinder. Imo to achieve self-regulation the valve needs to open briefly, less force from the hammer i.e. standard, as supplied, but slicked up so it moves smoothly each time. But we want the CO2 released into the barrel as quickly as possible, not after the pellet has long gone, with 177 the maximum size 3.50mm transfer port (must be smaller than the pellet). During reassembly align the barrel with the transfer port (using a drill shank), and the valve to the transfer port likewise, they can be assembled out of alignment. I have not worked with the long barrel, only the 177 pistol but have got a very respectable 4.6 ft lb which is ideal for a target pistol and has delivered 55 shots of 480-490fps (spread 9fps) to a total of 75 shots over 400fps from the cylinder (which is rather more than it says on the box). If I could shoot better that kind of fps spread would provide very tight grouping. I did chrono the long barrel but foolishly did not record it. From memory 620-640fps or around 7 ft lb, with very accurate tight groups. With CO2 177 is usually most efficient, the pellet goes with more energy than 22. With PCP it is the other way round, PCP operates with over three times the gas pressure.
Yeah, I do not like the idea of a heavier hammer spring so that is why I lightened the poppet spring,... I get what you are saying about pressure holding the poppet closed but I did notice a difference with the lighter poppet spring. I also noticed how loose & sloppy the hammer is inside the tube :( I had visions of the hammer bridging up, dragging on the top of the tube then falling, banging around, all of which cost energy & may make for a marginally slower hammer,... Wonder if a shim sleeve could be made to close the gap between the hammer & tube ? I did try Moly grease on the contact points of the hammer & although I like Moly grease I found it got gummy so went back to oil,... Wondering about a powder like baby powder of corn starch for lube lol. I have a .177 & a .22 & yes I do believe I have over exhausted the .177 at the port & barrel port :(
@@davidyummus6259 The hammer is a sloppy fit but that does not matter. It needs to fly down the tube without hanging up, nor much friction. I took the burrs off with a home brew 'flap sander' and polished up the edges of the various slots with a diamond rod. Not mirror polish just smooth enough not to catch. The hammer itself received a little attention to take sharp edges off but leave the sear release crisp. If you polish the sear ensure it remains at the correct angle, it really requires a jig to do it. There is moly grease and moly grease. The cheap stuff is as much use as boot polish. Pukka Moly-Slip is very expensive. It is only a non-stick surface coating to be used very sparingly, it is not really a lubricant. Gun moly is better than the nasty car stuff but still feels gritty to me. Gun oil has a lower viscosity than grease. Probably a better choice of lube here but only a drop or two not dripping wet. If you put moly on the bolt, it goes all over your hand.Metal to metal wants light machine oil but the tip of the bolt where it goes through the O-ring wants silicone oil. I have measured my stock transfer port as 9/64-inch which is 3.57mm and only nominal 3.5mm diameter. I have noticed some after market ports are too tall to close breech block to action tube properly. Here I would stick to genuine spares which are available in different diameters according to geographic market, if you can obtain them (hearsay Belgium gets a 2mm TR but UK gets 3.5mm)
Hi Jeff and other enthusiasts. Thank you for this excellent info. I studied Physics too and view my air guns in that context. I think people would love for you to make some videos about air guns, leveraging your physics/engineering knowledge. I'm working hard to get some out. I am brand new to these Diana's but I think they are really great, like an evolved Crosman. Cheers!
I had an issue one where i used too much grease on a blow forward paintball gun bolt when I was quickly breaking it in and just not worried about it. Stopped unit from working at all. So I went the other direction. Instead of using excess of the factory grease, I changed from grease to silicone oil (its all silicone in these things) and that was part of the solution. Unit is modded very high power for less lethal use so needs more frequent maintenance/lubing, but the bolt can fly plenty fast now. In your case since you are concerned about the forces at edge contact points from an askew hammer, I don't know if my situation applies. You might see a speed/performance increase, but your exposure to that contact point friction might be increased and maybe by a lot on a bad way. Grease might be required if there is a lot of piston/slide play. Interesting problem. I don't think a shim of any material would work at all, but thats a big fat guess.
@@maxhauler whilst I have the gear to make movies, I'm really not into vlogging. But yes I think to understand how an airgun operates we have to look at it from a physics-engineering perspective - how the gas is released through little tubes to push an object out of a tube. There are some maths that tells us what may happen but we do not generally have to run the numbers.
I think there will be flow from the capsule into the reservoir in the valve body until the pressure will equalize, if there is any pressure difference gas will keep on flowing until it will equalize. But the temperature will drop as the liquid CO2 vaporizes in the capsule, and the lower temperatures will translate to lower pressure until the capsule warms up again by absorbing heat from the ambient. Also once most of the CO2 from the valve reservoir has escaped trough the transfer port, flow from the capsule into the valve can be considered as negligible, for the amount of time the valve is open, because the diameter of the passage in the piecing needle is tiny compared to the transfer port.
@@aldogalbusera710 The original seal is a custom seal but I have been using a basic black nitrile O'ring very successfully :) The size I use is 9mm outer diameter x 5mm inner diameter which gives you a thickness or "cross section" of 2mm.
@@davidyummus6259 I had already tried a similar size (10 × 5 × 2) but when I tighten the golden screw the internal diameter tightens. he keeps by ear but if I leave the can under pressure for a couple of hours I find the gun unloaded. i used a round section oring for this i ask you if you use it flat
Yes. I could not buy the original seal so I now use an Oring. It is a 2.4mm Cross Section (thickness) with a 9mm outer diameter. www.ebay.com/itm/266070641342?var=565924710019
Mate only lessen your valve spring if your going to increase the volume of your air res ,ie needs to stay open lo ger to get in more air I've an smk victory, and it's a beast since I made my a res bigger and opened up my ports to 3.8mm ....but more power means less shots ..Good luck
Maximum port size for 177 is 3.5mm or the pellet falls into the hole. For 22 that would be 4.0mm with 4.5mm pushing your luck. If you polish the action tube and hammer up you can get more power with more shots. The hammer moves faster, less resistance.
in the U.K. we are only allowed 12 Ft Lbs of pressure in a air riffle and 6 Ft Lbs in a pistol i have both of these cp2 and a PP800 both are good enough for a bit of vermin and target shooting if we went above the Legal limits its up to 5 years inprisonment i am fine with my guns as they are when you get into the realms of trying to upgrade power you could do more harm than good to your gun just be happyt with what the manufacturers have produced..
In .22 & Rifle configuration, this gun now produces more than 10 ft pounds of muzzle energy, almost 11 on a good day & has done so for a couple of years now & is still shooting perfectly,... The Manufacturer has not produced the gun with limits, your Government has ;)
Hallo David, danke für Dein Video. Leider konnte ich nicht alles verstehen. Ich kann sehen, dass Du als Kapseldichtung keine originale Dichtung verwendest, sondern eine O-Ring. Bitte sende mir die Maße dieses O-Rings zu und auch aus welchem Material er besteht, da Co2 sehr agressiv auf die meisten Gummisorten reagiert. Danke und Grüße aus Deutschland
Der Ring hat einen "Querschnitt" (Dicke) von 2 mm, einen Außendurchmesser von 9 mm und einen Innendurchmesser von 5 mm, das Material ist gewöhnliches Nitril.
Vollständige Liste aller Größen, die ich verwende CO2-Dichtung (unter dem Gewindering): 2mm Querschnitt (dick) - 9mm x 5mm .177 Bolzenverschluss (am Ende des Laufs): 1,5 mm dick - 8 mm x 5 mm .22 Bolzenverschluss (im Laufende): 1,5 mm dick - 9 mm x 6 mm Laufanschlussdichtungen (2x) 1mm dick - 9mm x 7mm (fester Sitz) Messing Anschlussdichtungen (2x) 2mm dick - 10mm x 6mm Innere Zylinderdichtung (hinter dem CO2-Einlass/der Einstichsonde) 2 mm dick - 8 mm x 4 mm Zylinderdichtung (hinter den Gewinden zur Abdichtung der 2 Zylinderhälften): 2 mm dick - 14 mm x 10 mm Nitril-Ringe Übersetzt mit www.DeepL.com/Translator (kostenlose Version)
Hello Sir , im about to get a Diana Chaser myself and i wanted to ask if the valve is hard to remove from the Body ? Are there any special tools needed ? Could you maybe make a complete disasembly video? There is not a single one on youtube for the Chaser . Thanks Sincerely Daniel
Yeah, I should have done a disassembly video lol. One single screw in front of the trigger guard holds the stock on, remove that & with some pressure on the front of the CO2 chamber will remove the stock,... First thing I do then is wrap some masking or duct tape around the trigger housing to keep the little pins in place so they don't fall out. Next you will remove the single shot tray which is where you load the pellet, it just slides out & is held in place with a small magnet,... Under that is a tiny screw, don't lose it lol & don't over tighten it when you reassemble because the hex is easily stripped, light pressure with a little blue Loctite is best. Next, you will see 2 hex screws under the cylinder/hammer tube, one in the very rear which may pop the rear cap off under a bit of tension from the hammer spring, don't panic if the hammer spring pops out,... The other screw in front of the trigger is short & once removed, the barrel with separate from the tube. The little port plus 2 o'rings may fall out but again, no big deal, they simply sit in place & need to come out anyway,... The cylinder should now slide out of the tube :) When reassembling, make sure the bolt is closed because the screw on the bolt needs to be in front of the screw on the hammer so the bolt pulls the hammer back to set the trigger. When you tear it down you will really appreciate the simplicity :) You don't need to swing on the screws, just a good "nip" as they say,... To open the cylinder, you will need to put the rear end in a vice or vice grips or adjustable pliers then I put a pin in the air port (not the screw threads) & twist it open,... You will scratch up the cylinder a little but it will be fine. Most importantly, make sure the rifle is not loaded & does not have CO2 in it obviously.
Three bolts. Remove the CO2 cylinder, leave the cap off. The trigger guard bolt to remove the grip/body. The one at the rear that retains the hammer spring wants to come out first, and the tiny one under the single shot tray, pull the bolt back to access. Collect the trigger pins from the floor with a magnet. To remove the valve, remove the transfer port and O-ring then one more screw holding the valve body. The valve should now slide out of the CO2 end. Beware small parts falling out. Collect the trigger pins from the floor with a neodymium magnet. Whilst you're there remove the pins, trigger and sear and secure them. Release the hammer draw screw and remove the hammer. Examine the 'action tube' and de-burr. Remove the barrel and reassemble with it aligned (3.5mm or 9/64 drill shank) to the transfer port, not skew-whiff. When putting the valve back in, align that to the transfer port too. Make a note to order more trigger pins and O-rings. The CO2 cylinder seal is rubbish but it is a funny cup shape not an O-ring, some soft silicone rubber type, order a spare. Collect the trigger pins from the floor. Make a note to cannibalise an NMRI machine for its electromagnet. You can compress the valve spring easily in your fingers but when some 850psi of CO2 in there the valve is held shut by that, estimate some 35-lb force needed, about 0.04 sq in for valve assumed. Back of envelope worked in metric, converted. The spring just makes sure the poppet goes back in the hole, it does not hold it shut.
I could be totally off, but my understanding with CO2 cartridges is that (increased volume) =/= (decreased psi). You aren't talking about a cartridge of CO2 gas being utilized here, it's *liquid*. The pressure produced when changed to gas is the 1k psi you're talking about (closer to 850 psi). So the volume of that gas chamber in the gun won't change the psi unless it's big enough to exhaust all of the liquid co2 at once (it would have to be HUGE). Like I said, just my basic understanding from playing paintball -feel free to correct me if I'm wrong.
I simply assumed that the measured CO2 in the chamber was "set" by volume to be enough to actually fire the pellet but with at least equal emphasis on not wasting CO2 for extra power to conserve enough for "shot count",... I assumed that the gun may not be popular or marketable if it had power of propelling the pellet at say 750 feet per second if you only got a dozen shots per CO2 Powerlet. I simply wanted to be sure that in the duration of the valve being open, the pellet got every bit of available CO2,... To put it simply, lets say that during the cycle of the valve being open after the hammer hits the valve stem, if the open valve is capable of letting out 2 cubic inches of air, I wanted to be sure that the cylinder held 2 cubic inches of air & any extra would be left over when the valve shuts,... Hope you understand my point :)
@@davidyummus6259 yes, I think all that logic is sound. I was just referring to your commentary around 5:46 of not knowing what the psi is in that chamber. My point is that regardless of its volume (unless it's absolutely HUGE) it should be the same constant 850 psi (or in your case you were saying 1k psi) unless somehow you aren't giving it enough time between shots to fill up to to that pressure (should be impossible with the rate of fire of this gun). There shouldn't be any "pressure drop" until your CO2 tank starts running out.
You should have got more likes for taking the trouble to make the video and explain, thanks Shane uk 🇬🇧, I might try on my cp2 it is running low on power , only 5.2 in rifle mode .177 and I get 36 shots per co2 , can be seen on my channel thanks shaneweightman
The lighter valve spring worked an absolute treat on my CP2. I also put in a stronger hammer spring and made the action horrible. Harder to cock. Harder to adjust the trigger to something relatively safe. I bought a Crossmsn Ratcather valve spring for about £3 and it was absolutely spot on.
The pressure inside the valve will always be equal to the pressure inside the co2 cartridge. Increasing the volume inside the valve will give you more co2 to push the pellet out of the barrel.
Yes,... I've taken a lot of shit from people about doing this but it's very simple,... The time that the valve is open from the hammer striking it is what determines how much air is behind the pellet,... The pressure is what the CO2 cartridge has & no more,... I simply wanted to supply enough air for the time that the valve is open, any extra will just stay in the cylinder after the valve closes.
Porting is something else,... I actually lowered velocity on my .177 version because I opened the ports to the same size as this .22 & I ruined it because it's actually lower in power now due to less pressure,... The .22 is great because the heavier pellet holds back to build pressure before it starts moving.
Too bad it's still not true, yes psi will even out. But with the same hammer and valve you've done absolutely nothing but voided warranty. If you want a stronger gun convert it to hpa or buy a real pcp. You get shit because it harms your performance not helps it.
@@matthew33721
Dude, loading the hammer simply smacks the valve stem harder,.... You still have the same load on the return spring during opening AND closing of the valve,... The hammer smacking the valve stem and the back of the air chamber harder simply smacks it harder,... Smacking it harder simply increases force on those parts
Hallo David, habe heute einen ORing eingebaut. Alles hat super funktioniert. Ich danke Dir nochmals für deine sachkundige Hilfe.
Grüße aus Deutschland von Harald
Sie sind herzlich willkommen.
Es ist nicht so gut wie die Original-Dichtung, aber einfach zu finden und zu installieren.
The reasoning on gas pressure is not correct for CO2. This is because inside the capsule there is no CO2-gas but CO2 liquid with only a small portion of CO2 gas under a pressure of 56 to 60 bar at room temperature. The moment the capsule gets pierced, the gas will fill the gas chamber and because the liquid will evaporate to fill up the extra room, the pressure will not drop. Up to the point that all liquid is evaporated, the pressure will stay almost the same.
However, during evaporation (which cost energy) the chamber will cool down, and you should therefore avoid rapidly shooting as cooling will lower the pressure of the gas. Shooting in 30 to 60 seconds intervals should avoid to much cooling down.
I've modded these in the past increasing the volume inside the valve increases the muzzle volocity sometimes it can be almost 3ftlbs increase as well as opening the valve port to 4mm as well as the tp and barrel I had a .177 cp2 when they first came out made this mod it went from shooting at 7ftlbs to 11.2ftlbs
Increasing the chambers volume will not give you a performance upgrade. Actually the opposite. I'd like to see your fps before and after because it does absolutely nothing for your performance
@matthewtunstill3372 reading your reply. This. Jay & I'm asking. Would it lower your. Fps. ??? If you hollow out the chambers valves & cut threads in half. creating more or. Larger volume of compressed air ???
@matthewtunstill3372 on my 1322. I cut 3 threads off. Creating. A slight bit more air volume space. , it went from 10 pumps at. 468. To 15 pumps to get same pressure & shot. at. 486. , then installed new 14.6 in barrel. , slightly. Barely. Drilled. Exhaust port , mabey 1. mm larger & then some trigger adjusting to about. 1.3 lbs & then shot at. 613 612. 607. 609 610. 615. & that's as far as I'm going for now anyway, I'd like to see. 700. But that's a short ways off I think. If possible , but your thoughts. If. ya don't mind. ???....
Your thinking right you can also trim that pop it down to increase a little more to increase space in the valve it only needs enough to hold the spring on the tip .💯🎯🛠️😉
It might be true that increasing valve volume increases performance. The reason is simple. Co2 from the capsule has to go in the valve through small tiny puncture pin. During a shot action it has probably no time to go to the system. Increasing valve opening time ads some more gas to the barrel but it is not the gas from capsule. Indeed it looks like decreasing small spring tension is the way to go rather then beefing up the bigger one.
You will find more info on the generic "CP2" but most of the mods are to increase power not improve efficiency.
Being a retired physicist-engineer the first thing I did was strip my CP2 down and examine it. Oh dear. Decent parts but poor fit and finish at the factory.
The hammer /must/ slide smoothly so it delivers the same force each time. Burrs in the 'action tube' should not be there. polish them out with a long home-made flap sander. The rifling had a few burrs too, the long wire barrel brush. That alone should make the airgun more efficient, greater fps, less spread, more shots per cylinder. The factory lubricants are poor, use quality oils and greases. Beware the tiny little screw that holds the breech to the action tube, it's what I call a bad engineering solution, it is not man for the job: do not force it tight. Hold breech block to the action tube (compress the transfer port) and nip the little screw up with the short end on the Allen.
The CO2 gas pressure holds the exhaust valve shut. The valve spring does practically nothing except keep the poppet in place when there is no gas pressure. With it on the bench you can open the valve with your finger. When it is full the vapour pressure of the liquid CO2 will exert nominal 850psi (it varies with temperature). The CO2 can self-regulate. The valve is a balancer between the pressure in the valve and the constant impact force of the hammer, the less pressure in the valve, the longer the hammer will open the valve, &vv. If you increase the power of the spring the hammer just releases all of the gas, there is no regulation, and hence wild grouping and an empty cylinder.
Imo to achieve self-regulation the valve needs to open briefly, less force from the hammer i.e. standard, as supplied, but slicked up so it moves smoothly each time. But we want the CO2 released into the barrel as quickly as possible, not after the pellet has long gone, with 177 the maximum size 3.50mm transfer port (must be smaller than the pellet). During reassembly align the barrel with the transfer port (using a drill shank), and the valve to the transfer port likewise, they can be assembled out of alignment.
I have not worked with the long barrel, only the 177 pistol but have got a very respectable 4.6 ft lb which is ideal for a target pistol and has delivered 55 shots of 480-490fps (spread 9fps) to a total of 75 shots over 400fps from the cylinder (which is rather more than it says on the box). If I could shoot better that kind of fps spread would provide very tight grouping. I did chrono the long barrel but foolishly did not record it. From memory 620-640fps or around 7 ft lb, with very accurate tight groups. With CO2 177 is usually most efficient, the pellet goes with more energy than 22. With PCP it is the other way round, PCP operates with over three times the gas pressure.
Yeah, I do not like the idea of a heavier hammer spring so that is why I lightened the poppet spring,... I get what you are saying about pressure holding the poppet closed but I did notice a difference with the lighter poppet spring.
I also noticed how loose & sloppy the hammer is inside the tube :(
I had visions of the hammer bridging up, dragging on the top of the tube then falling, banging around, all of which cost energy & may make for a marginally slower hammer,... Wonder if a shim sleeve could be made to close the gap between the hammer & tube ?
I did try Moly grease on the contact points of the hammer & although I like Moly grease I found it got gummy so went back to oil,... Wondering about a powder like baby powder of corn starch for lube lol.
I have a .177 & a .22 & yes I do believe I have over exhausted the .177 at the port & barrel port :(
@@davidyummus6259 The hammer is a sloppy fit but that does not matter. It needs to fly down the tube without hanging up, nor much friction. I took the burrs off with a home brew 'flap sander' and polished up the edges of the various slots with a diamond rod. Not mirror polish just smooth enough not to catch. The hammer itself received a little attention to take sharp edges off but leave the sear release crisp. If you polish the sear ensure it remains at the correct angle, it really requires a jig to do it.
There is moly grease and moly grease. The cheap stuff is as much use as boot polish. Pukka Moly-Slip is very expensive. It is only a non-stick surface coating to be used very sparingly, it is not really a lubricant. Gun moly is better than the nasty car stuff but still feels gritty to me. Gun oil has a lower viscosity than grease. Probably a better choice of lube here but only a drop or two not dripping wet.
If you put moly on the bolt, it goes all over your hand.Metal to metal wants light machine oil but the tip of the bolt where it goes through the O-ring wants silicone oil.
I have measured my stock transfer port as 9/64-inch which is 3.57mm and only nominal 3.5mm diameter. I have noticed some after market ports are too tall to close breech block to action tube properly. Here I would stick to genuine spares which are available in different diameters according to geographic market, if you can obtain them (hearsay Belgium gets a 2mm TR but UK gets 3.5mm)
Hi Jeff and other enthusiasts. Thank you for this excellent info. I studied Physics too and view my air guns in that context. I think people would love for you to make some videos about air guns, leveraging your physics/engineering knowledge. I'm working hard to get some out. I am brand new to these Diana's but I think they are really great, like an evolved Crosman. Cheers!
I had an issue one where i used too much grease on a blow forward paintball gun bolt when I was quickly breaking it in and just not worried about it. Stopped unit from working at all. So I went the other direction. Instead of using excess of the factory grease, I changed from grease to silicone oil (its all silicone in these things) and that was part of the solution. Unit is modded very high power for less lethal use so needs more frequent maintenance/lubing, but the bolt can fly plenty fast now. In your case since you are concerned about the forces at edge contact points from an askew hammer, I don't know if my situation applies. You might see a speed/performance increase, but your exposure to that contact point friction might be increased and maybe by a lot on a bad way. Grease might be required if there is a lot of piston/slide play. Interesting problem. I don't think a shim of any material would work at all, but thats a big fat guess.
@@maxhauler whilst I have the gear to make movies, I'm really not into vlogging.
But yes I think to understand how an airgun operates we have to look at it from a physics-engineering perspective - how the gas is released through little tubes to push an object out of a tube. There are some maths that tells us what may happen but we do not generally have to run the numbers.
I think there will be flow from the capsule into the reservoir in the valve body until the pressure will equalize, if there is any pressure difference gas will keep on flowing until it will equalize. But the temperature will drop as the liquid CO2 vaporizes in the capsule, and the lower temperatures will translate to lower pressure until the capsule warms up again by absorbing heat from the ambient. Also once most of the CO2 from the valve reservoir has escaped trough the transfer port, flow from the capsule into the valve can be considered as negligible, for the amount of time the valve is open, because the diameter of the passage in the piecing needle is tiny compared to the transfer port.
A drop of superglue on the 3 trigger pins keeps from losing them and you wont have to tape them up to keep them in place....
Nice :)
@@davidyummus6259 hi friend, can you tell me the exact dimensions of the o ring on the co2 canister coupling?
I would be grateful
@@aldogalbusera710
The original seal is a custom seal but I have been using a basic black nitrile O'ring very successfully :)
The size I use is 9mm outer diameter x 5mm inner diameter which gives you a thickness or "cross section" of 2mm.
@@davidyummus6259 ok thanks really.
is the oring you use flat or round?
@@davidyummus6259 I had already tried a similar size (10 × 5 × 2) but when I tighten the golden screw the internal diameter tightens.
he keeps by ear but if I leave the can under pressure for a couple of hours I find the gun unloaded.
i used a round section oring for this i ask you if you use it flat
Bonjour a 5 minute 27 sur la video c'est un bien un joint o ring qui fait votre étanchéité ? Merci
Yes.
I could not buy the original seal so I now use an Oring. It is a 2.4mm Cross Section (thickness) with a 9mm outer diameter.
www.ebay.com/itm/266070641342?var=565924710019
@@davidyummus6259 je vous remercie pour votre reponse, bonne journée
на шептало поставил пружинку от зажигалки дешевой и спуск мягче стал
Qual nome dessa peça que perfura a ampola de co2 , quebrou a minha e não tô encontrando-a
Mate only lessen your valve spring if your going to increase the volume of your air res ,ie needs to stay open lo ger to get in more air I've an smk victory, and it's a beast since I made my a res bigger and opened up my ports to 3.8mm ....but more power means less shots ..Good luck
Maximum port size for 177 is 3.5mm or the pellet falls into the hole. For 22 that would be 4.0mm with 4.5mm pushing your luck.
If you polish the action tube and hammer up you can get more power with more shots. The hammer moves faster, less resistance.
Td bem David sou do Brasil estou tentando tirar o vazamento da válvula da minha mais sem solução.
in the U.K. we are only allowed 12 Ft Lbs of pressure in a air riffle and 6 Ft Lbs in a pistol i have both of these cp2 and a PP800 both are good enough for a bit of vermin and target shooting if we went above the Legal limits its up to 5 years inprisonment i am fine with my guns as they are when you get into the realms of trying to upgrade power you could do more harm than good to your gun just be happyt with what the manufacturers have produced..
In .22 & Rifle configuration, this gun now produces more than 10 ft pounds of muzzle energy, almost 11 on a good day & has done so for a couple of years now & is still shooting perfectly,... The Manufacturer has not produced the gun with limits, your Government has ;)
Hallo David, danke für Dein Video. Leider konnte ich nicht alles verstehen. Ich kann sehen, dass Du als Kapseldichtung keine originale Dichtung verwendest, sondern eine O-Ring. Bitte sende mir die Maße dieses O-Rings zu und auch aus welchem Material er besteht, da Co2 sehr agressiv auf die meisten Gummisorten reagiert.
Danke und Grüße aus Deutschland
Der Ring hat einen "Querschnitt" (Dicke) von 2 mm, einen Außendurchmesser von 9 mm und einen Innendurchmesser von 5 mm, das Material ist gewöhnliches Nitril.
Vollständige Liste aller Größen, die ich verwende
CO2-Dichtung (unter dem Gewindering): 2mm Querschnitt (dick) - 9mm x 5mm
.177 Bolzenverschluss (am Ende des Laufs): 1,5 mm dick - 8 mm x 5 mm
.22 Bolzenverschluss (im Laufende): 1,5 mm dick - 9 mm x 6 mm
Laufanschlussdichtungen (2x) 1mm dick - 9mm x 7mm (fester Sitz)
Messing Anschlussdichtungen (2x) 2mm dick - 10mm x 6mm
Innere Zylinderdichtung (hinter dem CO2-Einlass/der Einstichsonde) 2 mm dick - 8 mm x 4 mm
Zylinderdichtung (hinter den Gewinden zur Abdichtung der 2 Zylinderhälften): 2 mm dick - 14 mm x 10 mm
Nitril-Ringe
Übersetzt mit www.DeepL.com/Translator (kostenlose Version)
@@davidyummus6259 Hallo David, danke für Deine Nachricht. Ich werde es demnächst realisieren.
Hello Sir , im about to get a Diana Chaser myself and i wanted to ask if the valve is hard to remove from the Body ? Are there any special tools needed ? Could you maybe make a complete disasembly video?
There is not a single one on youtube for the Chaser .
Thanks
Sincerely Daniel
Yeah, I should have done a disassembly video lol.
One single screw in front of the trigger guard holds the stock on, remove that & with some pressure on the front of the CO2 chamber will remove the stock,... First thing I do then is wrap some masking or duct tape around the trigger housing to keep the little pins in place so they don't fall out.
Next you will remove the single shot tray which is where you load the pellet, it just slides out & is held in place with a small magnet,... Under that is a tiny screw, don't lose it lol & don't over tighten it when you reassemble because the hex is easily stripped, light pressure with a little blue Loctite is best.
Next, you will see 2 hex screws under the cylinder/hammer tube, one in the very rear which may pop the rear cap off under a bit of tension from the hammer spring, don't panic if the hammer spring pops out,... The other screw in front of the trigger is short & once removed, the barrel with separate from the tube.
The little port plus 2 o'rings may fall out but again, no big deal, they simply sit in place & need to come out anyway,... The cylinder should now slide out of the tube :)
When reassembling, make sure the bolt is closed because the screw on the bolt needs to be in front of the screw on the hammer so the bolt pulls the hammer back to set the trigger.
When you tear it down you will really appreciate the simplicity :)
You don't need to swing on the screws, just a good "nip" as they say,... To open the cylinder, you will need to put the rear end in a vice or vice grips or adjustable pliers then I put a pin in the air port (not the screw threads) & twist it open,... You will scratch up the cylinder a little but it will be fine.
Most importantly, make sure the rifle is not loaded & does not have CO2 in it obviously.
Three bolts. Remove the CO2 cylinder, leave the cap off. The trigger guard bolt to remove the grip/body. The one at the rear that retains the hammer spring wants to come out first, and the tiny one under the single shot tray, pull the bolt back to access. Collect the trigger pins from the floor with a magnet.
To remove the valve, remove the transfer port and O-ring then one more screw holding the valve body. The valve should now slide out of the CO2 end. Beware small parts falling out. Collect the trigger pins from the floor with a neodymium magnet.
Whilst you're there remove the pins, trigger and sear and secure them. Release the hammer draw screw and remove the hammer. Examine the 'action tube' and de-burr. Remove the barrel and reassemble with it aligned (3.5mm or 9/64 drill shank) to the transfer port, not skew-whiff. When putting the valve back in, align that to the transfer port too. Make a note to order more trigger pins and O-rings. The CO2 cylinder seal is rubbish but it is a funny cup shape not an O-ring, some soft silicone rubber type, order a spare. Collect the trigger pins from the floor. Make a note to cannibalise an NMRI machine for its electromagnet.
You can compress the valve spring easily in your fingers but when some 850psi of CO2 in there the valve is held shut by that, estimate some 35-lb force needed, about 0.04 sq in for valve assumed. Back of envelope worked in metric, converted. The spring just makes sure the poppet goes back in the hole, it does not hold it shut.
I could be totally off, but my understanding with CO2 cartridges is that (increased volume) =/= (decreased psi). You aren't talking about a cartridge of CO2 gas being utilized here, it's *liquid*. The pressure produced when changed to gas is the 1k psi you're talking about (closer to 850 psi). So the volume of that gas chamber in the gun won't change the psi unless it's big enough to exhaust all of the liquid co2 at once (it would have to be HUGE). Like I said, just my basic understanding from playing paintball -feel free to correct me if I'm wrong.
I simply assumed that the measured CO2 in the chamber was "set" by volume to be enough to actually fire the pellet but with at least equal emphasis on not wasting CO2 for extra power to conserve enough for "shot count",... I assumed that the gun may not be popular or marketable if it had power of propelling the pellet at say 750 feet per second if you only got a dozen shots per CO2 Powerlet.
I simply wanted to be sure that in the duration of the valve being open, the pellet got every bit of available CO2,... To put it simply, lets say that during the cycle of the valve being open after the hammer hits the valve stem, if the open valve is capable of letting out 2 cubic inches of air, I wanted to be sure that the cylinder held 2 cubic inches of air & any extra would be left over when the valve shuts,... Hope you understand my point :)
@@davidyummus6259 yes, I think all that logic is sound. I was just referring to your commentary around 5:46 of not knowing what the psi is in that chamber. My point is that regardless of its volume (unless it's absolutely HUGE) it should be the same constant 850 psi (or in your case you were saying 1k psi) unless somehow you aren't giving it enough time between shots to fill up to to that pressure (should be impossible with the rate of fire of this gun). There shouldn't be any "pressure drop" until your CO2 tank starts running out.
Export ventile , 8.99 Euro.
You should have got more likes for taking the trouble to make the video and explain, thanks Shane uk 🇬🇧, I might try on my cp2 it is running low on power , only 5.2 in rifle mode .177 and I get 36 shots per co2 , can be seen on my channel thanks shaneweightman
The video is a bit long & not great quality but just wanted to share :)
Bulk
When people try to help by giving you a few pointers in Physics 101, maybe listen a little instead of being so aggressive.
Lmao 😂