preloaded pneumatic cartridge
Posted: Mon Jun 11, 2007 1:47 am
I downloaded a bunch of WW2 tank documentaries recently, found myself re-watching saving private ryan and digging up medal of honour allied assault, I have to say its re-kindled my interest in making a decent cartridge pneumatic.
As a matter of interest, I hooked up a length of 0.177 barrel to the pneumatic pengun project to see what the power would be like if I made a rifle-sized cartridge, the BB came out with considerable haste but only left a small dent in the bottom of a soup tin so not worthwhile power in my opinion and definitely not enough to cycle the action.
Therefor I concluded that the best course of action would be to scale things up to 3/4" calibre. I want the cartridge to use the same material as the barrel, this would solve alignment issues with "mass" produced cartridges and make fo a sleeker more realistic (to some extent) design. The launcher that would use it would have a spring-loaded bolt that would seat the cartridge in the breech and when it reaches the end of its travel, a pin on the bolt would strike the schrader valve and fire the cart. This would then fire the projectile and blow back the cartridge and bolt, to either recock it ready for a next shot or if a sear wasn't fitted, give full auto action.
The plan therefore is to make the cartridge first, to the design below, and evaluate the power potential. The volume is small but at around 350 psi I'm hoping it will give worthwhile "oomph". Watch this space
As a matter of interest, I hooked up a length of 0.177 barrel to the pneumatic pengun project to see what the power would be like if I made a rifle-sized cartridge, the BB came out with considerable haste but only left a small dent in the bottom of a soup tin so not worthwhile power in my opinion and definitely not enough to cycle the action.
Therefor I concluded that the best course of action would be to scale things up to 3/4" calibre. I want the cartridge to use the same material as the barrel, this would solve alignment issues with "mass" produced cartridges and make fo a sleeker more realistic (to some extent) design. The launcher that would use it would have a spring-loaded bolt that would seat the cartridge in the breech and when it reaches the end of its travel, a pin on the bolt would strike the schrader valve and fire the cart. This would then fire the projectile and blow back the cartridge and bolt, to either recock it ready for a next shot or if a sear wasn't fitted, give full auto action.
The plan therefore is to make the cartridge first, to the design below, and evaluate the power potential. The volume is small but at around 350 psi I'm hoping it will give worthwhile "oomph". Watch this space