SpudFiles

I've been thinking of designs for a piston for a co-axial pneumatic and I haven't found anyone using a check valve in the piston to fill the chamber rather than letting the air seep around the sides. Is there a reason for nobody using this idea? Thanks

People have done this but usually just drill little vent holes in their pistons because check valves add weight and are just one more thing to break in you're gun... good luck on you're launcher

Ahh that makes sense, I might put a bit of rubber over the end of the vent hole instead of a check valve. Also do most people make co-axial's servicable?

Serviceable is pretty much a requirement for piston valves. They need bits of spuds cleaned out, dried sticky apple sauce removed, re-lubricated, etc.

Would I still need to if I'm using foam rounds for it? It would be possible for me to unscrew the pilot valve at the back and spray in a bit of silicon spray to keep it lubricated.

I would still make it serviceable. My big co-ax would have been in the trash by now if I hadn't had made it serviceable... I've had to replace the rubber washer 2 times and even remade the entire piston once. BTW why are you going to shoot foam rounds? lol

I've just come up with an idea to make it look like I wanted and still be serviceable I'm using foam rounds for use against vehicles in airsoft, I'll end up using other stuff as well for destruction though

People use check valve pistons all the time... How could you not find one?

All I could find were piston check valves, I mustn't have been looking in the right places

Have you not found this?
http://www.spudfiles.com/forums/piston- ... rt,30.html

Ah, no but that's exactly what I was looking for, thanks I think I'll drill a hole and use part of the sealing face as a closing flap

All I could find were piston check valves

I thought that was what you were looking for.

That last post sounds like a good idea.

Yeah, sorry my wording wasn't very good. I meant a piston with a check valve to equalise pressure in the chamber. I think I'll just do the sealing face flap, it'll be like a simple, lightweight check valve.

That's what all piston check valves do.

Oh...
I've looked on google and cant seem to understand... is it kind of like a one-way piston vlave?