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samguy700
04-21-2009, 09:51 PM
...but i read somewhere that catriges have to be able to withstand UP TO 3000 psi, now i thought paintball guns have to be filled to aroung 3000 psi so it cant be hard to optain a pump which will pump it up to that, now here is my idea, you fill the cartriges with nitrous oxide or another propelant/flamable gas, and then put a primer in or some sort of ignition, so that when the firing pin hits the back of the cartrige the gas inside is ignited.
now provided you can stop the bullet from flying out of the cartrige then this could make refilling cartriges a lot easyer in countries where it is near impossible to optain black powder or the ingridients to make it, it would also do just aswell as smokeless powder, seeying as propane methane etc dont leave a big cloud as they burn.
now you may at this point be thinking "yes kid but the bullet will fly the fuck out"
picture a shotgun (slug variety) shell except the top bit that is crimpeled is made of metal now picture this idea in say a 45 cal


crap paint pics coming

The Savage
04-21-2009, 11:26 PM
Most rifle rounds opperate at around 50,000 - 55,000psi. Even shotguns which are known for low pressure operate around the 10,000 - 14,000psi range.

Filling a case with propane or w/e isnt going to generate enough power to drive the bullet through the barrel, and if it DID actually make it out of the barrel, getting shot with it would be more of an annoyance than anything i think.

blue_monday
04-22-2009, 01:05 AM
i feel this is relevant somehow
http://www.youtube.com/watch?v=POCGiy5VpxI

samguy700
04-22-2009, 03:55 PM
thanks ^ i wish i could 5* you like on rotteneggs.
if a paint ball tank will fire .30 cal fast enought to cut a 2 by 4 in half and fast enough to go clean through a metal bucket then my idea could be similarly lethal
edit: sorry to be a smart ass but:
by original poster in the comments:
Hi.
In any caliber Iīve saw it shooting (.308 with .32 ACP slugs, .355 with 9mm Luger slugs, .451 with .45 ACP slugs) it shots at the same velocity: under 3300 psi of air-pressure it has a MV of 790 fps and 311 FPE at the muzzle.
You can estimate itīs velocity at any distance by comparing a Tommy Gun SMG in .45 ACP - it seems to be very close in the two guns.
You get similar velocity and energy from the Caselman and a (conventional firearm) Thompson in .45 ACP.
Not bad for an air-gun, uh?





A .50 Browning heavy machinegun cartridge (12.7x99mm) have up to 75.000 PSI at the peek of the pressure, but it lasts only a fraction of a second, we can say that the relative constant pressure inside such a barrell of, say, 42", itīll be something like 15.000 PSI;

blue_monday
04-22-2009, 06:48 PM
take a look at these too
http://www.airforceairguns.com/index.html
http://www.quackenbushairguns.com/

Venom
04-22-2009, 11:09 PM
http://www.uttings.com/Categories/Shooting/AirCartridge/Brocock/bacs.gif

http://www.uttings.com/Categories/Shooting/AirCartridge/Brocock/

The Savage
04-23-2009, 06:21 AM
edit: sorry to be a smart ass but:
by original poster in the comments:
Hi.
In any caliber Iīve saw it shooting (.308 with .32 ACP slugs, .355 with 9mm Luger slugs, .451 with .45 ACP slugs) it shots at the same velocity: under 3300 psi of air-pressure it has a MV of 790 fps and 311 FPE at the muzzle.
You can estimate itīs velocity at any distance by comparing a Tommy Gun SMG in .45 ACP - it seems to be very close in the two guns.
You get similar velocity and energy from the Caselman and a (conventional firearm) Thompson in .45 ACP.
Not bad for an air-gun, uh?

A .50 Browning heavy machinegun cartridge (12.7x99mm) have up to 75.000 PSI at the peek of the pressure, but it lasts only a fraction of a second, we can say that the relative constant pressure inside such a barrell of, say, 42", itīll be something like 15.000 PSI;

but i read somewhere that catriges have to be able to withstand UP TO 3000 psi

I read your post again and i'm still not getting a clear picture of what you're talking about. Do you mean take your standard, say 9mm case, and load it normally except for instead of gun powder fill it with NOS (provided you could keep it in there)? and then fire it through a regular firearm?

If so, i'm thinking you would need to generate simmler pressures to reach the same velocities which for 9mm is around 30,000psi for a 115gr jacketed bullet at just over 1000fps. But the other pressure issue (Which you might of been refering to with the 3000psi comment?) is the preasure of the gas you would need to push into the case to make enough energy to drive the bullet. You'd need a very aggressive crimp on the projectile and primer, even then you might run into buldging issues, especially with longer cases and thinner walls.

Correct me if i'm wrong, but the links don't really apply since they're either super-sized air rifles and/or custom made and opperating completely different to conventional weapons...

then this could make refilling cartriges a lot easyer in countries where it is near impossible to optain black powder

samguy700
04-25-2009, 12:13 AM
I read your post again and i'm still not getting a clear picture of what you're talking about. Do you mean take your standard, say 9mm case, and load it normally except for instead of gun powder fill it with NOS (provided you could keep it in there)? and then fire it through a regular firearm?

If so, i'm thinking you would need to generate simmler pressures to reach the same velocities which for 9mm is around 30,000psi for a 115gr jacketed bullet at just over 1000fps. But the other pressure issue (Which you might of been refering to with the 3000psi comment?) is the preasure of the gas you would need to push into the case to make enough energy to drive the bullet. You'd need a very aggressive crimp on the projectile and primer, even then you might run into buldging issues, especially with longer cases and thinner walls.

Correct me if i'm wrong, but the links don't really apply since they're either super-sized air rifles and/or custom made and opperating completely different to conventional weapons...


a poster posted below me that 3000 psi wasent enough so i posted the thompson to point out it was

The Savage
04-25-2009, 03:08 AM
nm screw it

@@@
04-26-2009, 02:36 AM
thanks ^ i wish i could 5* you like on rotteneggs.

:facepalm:

ilovechronic
04-28-2009, 03:32 AM
The chamber is where the strength is at. If you were to fire a cartridge outside of the properly made and proper cal chamber the case would probably burts/rupture/crack/stress.

this is what happens whan you have an obtruction in the chamber/bore. For example if you dunk your gun in qwater an dthe tried to fire it with out shaking out the water from the chamber you would have a k'boom on your hands (literally).

samguy700
04-28-2009, 10:13 AM
The chamber is where the strength is at. If you were to fire a cartridge outside of the properly made and proper cal chamber the case would probably burts/rupture/crack/stress.

this is what happens whan you have an obtruction in the chamber/bore. For example if you dunk your gun in qwater an dthe tried to fire it with out shaking out the water from the chamber you would have a k'boom on your hands (literally).




so you cant fire guns underwater

ilovechronic
04-28-2009, 10:13 PM
so you cant fire guns underwater
Some you can. there are so many designs that it depends. the more important thing is that the chamber is OMPLETELY submerged with NO air bubble between the cartridge case and the chamber.

There are vids online of people shooting them under water. Also they did it on myth busters and I believe the 12 ga bursted and cracked. That could be because they didnt get all the air bubbles out.


the SEALS train for combat while in the water.

how lethal is it going to be under water?
Not very. Maybe if whatever you are shooting at is no farther than a few feet from the muzzle.