Here is a rough diagram of my plan.

Now talking about having minimal space behind the piston, what about having space that the piston can't travel? I'd like to run some pressure hose from the T at the back of the tank, to my valve, about halfway down the gun, will the cubic volume of air be a problem if I do that? Also, can I use a sc...

Ok I searched for this and got like a 3000 hits, none of which seems to answer my question(s) I am building a coaxial piston gun, and Have a normal end cap, I have seen that several of the guys on here who have made these, seem to use screws to seal the end cap in place, so that it can be removed fo...

looks good to me, but I'm no expert.

my owly question is this, is this supposed to be a shoulder fire weapon? because (atleast by the diagram) you have no stock, and the body looks a little cumbersome to handle/shoot from.

just my .02

does it leak at all, or have any problems?

also, how are QEVs usually (idk the proper word vented,released,fired????) triggered?

Do you know if they make a slide/sleeve valve that is pressure rated to 400 psi?if so, it would be EXACTLY what I've been looking for. I spent about a half hour on the net looking but haven't found anything yet

thats for paintball ones though, the "professional" ones you would use for co2 industrially go for 50-100 bucks US

you can buy a paintball reg for a the paintball type tanks for about 10-20 bucks on ebay. also, are you familiar with check valves? would that work in place of a ball valve? pressure gets yay high, check valve shuts, using the qev I release pressure through the barrel. checkfill reopens from pressure.

yeah, and I definitely want the highest pressure, but I was hoping for the best of both worlds :lol: like I said I will probably end up going with your suggestion. But I want to search for awhile yet, see if I can't find a similar valve to what I was looking at but that can handle higher pressure. :...

that seems the simplest, doesn't quite provide the "point and squeeze" trigger I was looking for though

oh well, that probably what I'll end up doing. Gonna waste another hour or so looking on the net for a valve that would reach the above criteria before giving in though 8)

are qev's three way, or would I have to put a valve between my pressure source and tank that would be shut between each shot
looking into qevs now! LOL

The valve I am looking at is only rated to 120 its product number 6464K12 at MCmaster.com, I wanted to use that or something like it, so I can keep constant co2 pressure in my pressure chamber, and then seal the inlet, and release the pressure to the barrel. beggining to wonder if that will work or ...

compression like you would use on a copper pipe? would that work on steel ( I was under the impression those were for soft metal piping) if they work, it would be awesome! 8) also while I have a ear, if I'm making a barrel roughly 3/16" in diameter and about 2 3/4-3 feet long. and running the pressu...

hey quick question, does anyone know anything about running high pressure through a hose clamp temporarily? The piece of pipe I want to use for the barrel of my rifle isn't threaded at all, and I was thinking maybe I could use a couple of hose clamps to secure a thick rubber hose to the pipe and the...

no you always start small, but (shameless spamming ahead, you been warned!) if you join an alliance such as toh you can get aid to give your nation a jump start and info on how to make things work best/smoothest