SpudFiles

you need a one-way valve/check valve there...

just an advice for all of you - use push-to-connect fittings and tubing... 4mm OD polyamide tubing has a pressure rating of up to 50 bar

I considered a check valve, but considering gas only ever flows in that one direction, it wouldn't make a difference.

ohhh yeah sorry... you need this -> http://www.elektro-automatic.com.pl/cat ... _53_74_286

IIRC it's called a needle valve in english...


IMHO you should get a 3 way valve if you want a semi auto... even something as simple as this -> http://www.elektro-automatic.com.pl/cat ... _53_74_291

or this -> http://www.micropolska.com.pl/zawory_me ... ecznie.jpg

you can add an air cylinder and you've got a semi auto

recently I realised that my semi auto operates more less in the same manner as commercial paint-ball guns...
just have a look -> http://www.zdspb.com/media/tech/animati ... r_7fps.gif

you can see that there is a 5 way valve and the bolt is in fact a small double acting air cylinder... everything is almost the same... even the main firing valve is similar to a QEV... on the surface you think it's different but the way it works is the same

notice that you'd need machined parts to build that... but mine does the same and what makes it different from a basic QEV gun is an air cylinder and a 3 or 5 way valve

Well, I'm going to stick with what I've got for now. Maybe if I come across some extra cash and feel the need to upgrade then I'll add an air cylinder and a 3 way valve. Until then I'm just going to (hopefully) get the blow forward finished and have fun with it.