piston pistol idea

[keep_it_real]

http://science.howstuffworks.com/revolver2.htm

You can use a ratchet and prawl similar to the one in that link.

http://www.spudfiles.com/forums/revosemi-t7694.html
Theres the one I made. Don't know if you've seen it yet but I would go with the design in the first link.

UNLESS... Your best bet would be to make a revolver that you just turn by hand and secure it with a sliding bolt similar to the Rev-X: http://www.advancedspuds.com/revolverx.htm

Edit: go to boltsniper.com and look at the pistols he made. They look very realistic. I forget what he modeled them after though.

[us sniper]

I was wondering what valve to use to make it look like a revolver.To make it turn I am using parts from a cap gun.

[turbohacker]

Your pressure is only going to build up behind the piston, not chainber.

Your only other option is a piolet valve, it has to be just the right size for maximum efficency.

[us sniper]

I do not understand what you are talking about. For the first pistol I am going to use a piston valve. I am asking what valve would make it look the most like a revolver.

[turbohacker]

The piston valve you show will not fill up the chainber because the o-rings will trap the air behind the piston.

[Jolly Roger]

Sorry, I forgot to mention it must have some sort of somewhat restricted flow into the chamber. You could simply drill a hole in the piston (not the middle) small enough so it will still go back but big enough to fill the chamber quickly. Just like a normal piston co-ax though the "leakage" is through the piston, not around it. And depending on how big you make the pilot area, if you place a large valve on the back, you will only be 'wasting' that area of pressure, give or take a little. And honestly, it wont be that much really.

[keep_it_real]

us sniper: I would go with a piston valve in a tee and the chamber can double as the grip. For the pilot valve I would put a sleeve valve on the back. This can be found on page 435 of mcmaster. This will also make it semi-auto (just the valve not the loading system). You could construct the trigger something similar to clide's semi auto paintball gun: http://www.spudfiles.com/forums/semi-auto-t160.html