Design in need of input

[Goats spudz]

what if I were to add a check valve to the tee into the coax chamber so that air could only go in, and enlarged the piston pilot/QEV chamber area, while making an internal rear bumper that would stop the piston from traveling back too far, but still letting air pass through?

Something like this:

That would be Suupeer unefficient, when you fired the air infront of the piston would fire the round and the air behind would travel all the way around that network of pipes to the check valve then enter the barrel, a traditional (traditional hehe) coaxial would be better suited

[foilboy]

Thanks for the replies guys.

Mr.Crowley, I did actually think about the whole "projectile being downrange before the pilot pressure gets there" problem. I was kind of just hoping I would be wrong

Guess it's time to let this brainstorm fizzle out. Thanks all!

[jackssmirkingrevenge]

Never made it but you could exhaust directly to the barrel: