SpudFiles

I think we should start a thread to list and generalize the different passive designs used in hope of producing full auto. generally what I mean by passive is anything with a circuit board is out.
I think they can all be categorised into the following categories
piston clide's semi/full auto golfball cannon or a home made popoff relief valve
sprinkler/qev a poppet piloted qev, a sprinkler valve triggered by a pressure switch
hammer valve blowforward or blowback poppet

QEV/piston piloted by a slide check for a simple semi-auto, add a ram for full. Drawback is that this design has nothing to prevent the chamber from dumping out all air pressure.

And I just posted a theory to conserve that air in your chamber:
The shutoff piston.

Have a look at this thread.

oh yeah that thread