help with semi automatic airgun

[Nikolai1939]

Hello there. I'm planning to make a semi automatic air carbine, but I'm not familiar with QEVs and air cylinder pistons, so heres two questions:

1- can I use this style of blow gun to divert pressure to the pneumatic pistol and thus push it forward? Or can I only do it with a solenoid 3 way valve?
2- can I connect the reservoir directly into the blowgun handle like in example A by closing off the QEV air entry (marked as 1) and putting a shredder valve at the back of the reservoir to fill it up from there? Or would it need to be done like example B?

[farcticox1]

I did the piston thing with my 10mm, it ran off 2 valves, was pretty complicated for what it did but worked great.

[farcticox1]

This turned into a semiauto by making a simple spring loaded piston, I'll find some pictures. If I was going to build another semiauto I would do this again.
viewtopic.php?f=29&t=26658
This is how the piston works, the block is aluminum.

piston.jpg (11.86 KiB) Viewed 13641 times

I made it from a piece of nylon and a bolt

20200822_190607.jpg (19.39 KiB) Viewed 13641 times

[FerdBlu]

You may get away with no bolt at all. I have done that multiple times. Just seal the magazine with the barrel so that no air can escape. This makes the whole thing more powerful and simpler

[quinn whitsitt]

i whould recomend placing one way valve fasing oposite directions with a tee in the middle with a one way valve at the bottom of the tee facing down into a air hose adapter with an air house on the adapter that feed back into the air tank with a nother one way valve that faces towards the air tank with this addition you should be able to save most of the air note though that in order for this system to work it should be reltivle fast and the faster sed projectile goes the faster the cylic rate whill be

[quinn whitsitt]

nice job everyone