pressure 22air vs 22LR
Hi, can anyone tell me how is it possible that a .22 airgun (modified condor for example) can shoot almost at same velocity (1100 fps and more) as 22LR when using same 40grain bullets. The pressure which airgun operates is 2000-2900 psi vs pressue in 22lr chamber is arund 22000 psi. My guess would be that when bullet travels down the barrel airgun gives that 2000psi all the way to the end vs 22lr gives this 22000 psi only at the beginning, am i on the right track?
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Spooky would never send anyone detailed drawings or anything but he always seemed to have no problems in posting great detailed pics of his work that would do just about the same thing. I lost all my pics of his works due to a hard drive failure and now I see that his pic links are no longer good ones. (
I do remember seeing some valve drawings from him on how he did the low back pressure valve in that one fletchet gun he made. Someone had linked them to me back when I was posting my own thoughts on how it could be done. His idea required a hole at both ends of the tank though so it wasn’t usable in our style of guns.
When I first heard about “Spooky” I did a search on him so I could find more of his posts. The guy is a genius when it comes to airguns. That other Walter was in more than one thread always asking for more information and specs.
There was a link in this thread to one such thread posted by Bubba.
http://www.practicalmachinist.com/vb/showthread.php?t=127421&highlight=airgun
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Thanks for the link. Thaet was me asking for more info.
The performance Dave was claiming had my interest. The machine work of his gun was indeed amazing. I had forgotten where the maker of that gun had posted. A very much Airforce style with a layout much like the Edge.
IIRC that gun was indeed the inspiration for Bubbas gun.
Was never able to get any information from Dave as he has to maintain the secrecy agreements he made. His story anyways.
Thanks again. I had forgotten that forum from so long ago… 1 1/2 years
Cheers,
Please post some of those pics if possible. What a beaut.
Walter..
Very nice and PLEASE post more of your airgun ideas. Very happy to digest them.
Walter….
I think Shadoh just owned Walter – not “our” walter.. That “other” Walter offcourse 😉
Maybe there is more than one then. Ive seen that name on many airgun and related forums. Usually asking how something was done and mostly about airgun valves.
When I first heard about “Spooky” I did a search on him so I could find more of his posts. The guy is a genius when it comes to airguns. That other Walter was in more than one thread always asking for more information and specs.
There was a link in this thread to one such thread posted by Bubba.
http://www.practicalmachinist.com/vb/showthread.php?t=127421&highlight=airgun
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If thats not you then my mistake but it sure sounds like you. At any rate that Walter squeezes all the information he can out of “Spooky” regarding his guns and especially airgun valves on several different forums.
I am indeed WalterGlover of Alberta, Canada 🙂
I have no idea who Spooky is.
There are very few of us about so if you could let me know who he is I would be grateful.
BTW I have yet to squeeze information from anyone lol, it is usually the other way around!
Are you not WalterGlover from Alberta Canada? I was talking about Dave(Spooky). He has built tons of one off airguns including high powered and high fps guns.
If thats not you then my mistake but it sure sounds like you. At any rate that Walter squeezes all the information he can out of “Spooky” regarding his guns and especially airgun valves on several different forums.
no get this one???????
who’s spooky?
This is what I know! an airgun is doing well to get 1100fps with a bore-weight roundball in all calibers. Do get faster the projectile must be lighter
To get more power the projectile is of course lighter with a corresponding drop in velocity. In my experience it is good to achieve 1000fps with a 2x bore weight and 900 with a 3x bore weight.
So for the caliber we are chatting about bore weight is 16 grains so to achieve 1000fps with a 32 grain pellet is amirable and to achieve 900fps with a 48 grain bullet would be amazing.
But to somehow get 1100fps with 40 grains on air….. NOT!
Cheers,
Walter…
With a heavier slug and the right valve I think its doable. Having chatted up “Spooky” yourself Walter I would think you would know that.
subsonic 22lr at 1100fps = 107.5fpe
hottest Condor numbers 28 gr at 1100fps = 75.25fpe
fair bit of difference like 150% more powerful…..
Nope… as you so kindly pointed out earlier when others missed the mark somewhat – This thread is about .22’s 😛
NASA achieve their velocities because they are firing in a vacuum.
My thinking was just that you could make an airgun to shoot the same velocity as a .22lr and yes you can shoot over the speed of sound with an airgun pellet / slugg but …… whats the point if you cant get the same ballistic coefficient of a live round. Ive yet to see any airgun calibar to calibar manage to come close to a firearm but if someone has a link i would very much like a read it ?. Alot of the high powered airguns are still using lead balls from what ive seen! , abit of an old technology. Yes people are ” playing with bullet shaped projectiles ” and using .22lr barrels and bullets but ive yet to see someone whos says their going to bin their Rimi for their new airgun ?
How dose the ballistic coefficient of a lead ball compare to a modern round ? im thinking not good ? ( may be wrong on that …hehe ) . I didnt answer the question partly because im a bit dim and im thinking more about whats leaving the barrel and how its going to arrive on target , which is more the problem than the gun side of things as far as i can see. Projectile design is where i would spend the time and effort !.
So im with Voltar_1 on this ,thou im sure we would both like to be proved wrong !.
Ah Ha, guess I’ll have to do it. Would the very few 220 gr. .455 cal. not qualify? Seems I have seen test up to 1800-1900 fps at a 5000-6000 psi fill. (NOT An AirForce gun, but custom one of a kind rifle). (Check out some of the big game hunting on youtube with an air gun. Including a fully grown Bull Buffalo.) Perhaps I’m remembering incorrectly. I’m a little old you know! I know that NASA has gone over 1000 grains at over 20,000 psi. The velocity was off the charts. They are looking for up to 55,000 MPH to simulate space particles. I’m way too tired right now to figure it to fps. 😉 Lol!
Heading out the door to look at another Zeiss! 😀
Mike
The facts I refer to Mike is that no-one has attained 1100fps with a 40 grain bullet in .22 cal from a PCP.
So as far as the theorizing goes it is a non-starter due to the fact no-one has achieved this with an airgun.
Walter…
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I do remember seeing some valve drawings from him on how he did the low back pressure valve in that one fletchet gun he made. Someone had linked them to me back when I was posting my own thoughts on how it could be done. His idea required a hole at both ends of the tank though so it wasn’t usable in our style of guns.
Spooky would only hint at performance in the few posts he made.
One thing he mentions is that the projectiles were fleschettes which we do not know the weight of nor the bore friction they had. So his 1600fps airgun was somewhat suspect as was his 450BAR fill pressures.
His gun was beautiful but I do not recall any sketchs of the workings inside. Too bad the links are bad now. Was hoping to go refresh my memory of that gun.
I do recall that the tank was a reservoir tube so he was in control of the pressure design and fastening methods. Pretty cool idea for assisting the valve opening forces for sure.
So we still do not have any definitive facts regarding a 1100fps 40gr PCP
Would love to hear about one 🙂
Walter….