He is using a QEV and a 3 way valve with a bolt action system for loading BB's. There are tons of people here who use similar valve systems so you should look through the airsoft and pneumatic sections of the forum.[/url]

Instead of a slide valve, get a normally open push button 3-way DCV. Like something from here but a bigger size if you need better airflow.

Looks like it should work unless you have the QEV in backwards.

Look at JSR's post on this thread

For a barrel, buy a airsoft tightbore. You'll get good performance with those. It'd be around $30 for a 650mm long by 6.03mm ID one.

It doesn't look like its behaving like a regulator so it either has a defect or is just a valve. You should ask the guy at the store.

You would need a large air source tank and a smallish air chamber. A 3-way DCV or multiple ball valves would be needed to pilot it.

Sorry for bumping this but what is the CAD program you used?
Thanks.

I've heard that ABS cracks instead of exploding and shooting shrapnel everywhere so it would probably be safer. SCH 40 is much more common though.

Damn that thing is huge. Don't think I've ever seen a gun in the MJ range. Impressive.

How can you calculate approximately how many shots you'll get out of a regulated source. For example, if you have a gun that has a 5 cu. inch chamber and shoots at 120psi, how many shots would a 50 cu. inch tank at 3000psi provide. Would you just multiply the 50 cu. inch*3000psi to get 150000cu.in*p...

I'd say compressor. I have a (very old) 30gal one and it is useful for almost every project, even if its just for clearing junk out of things I cut. Of course, if you're building any kind of pneumatic launcher, its a must-have.

For the air use, I plan on using a 1 cubic inch chamber at 100 (regulated) psi (GGDT says that'll give around 500fps with my setup). Assuming the air source is a standard 3000psi 48 cubic inch tank, that is 144000 cubic inch*psi. The airgun should use 100 cubic inch*psi, therefore theoretically givi...

Alright thanks.

Would the bolt moving back cause a performance decrease? Or does it just depend on how tight you make the spring