I like it, but how dus the valve work?

Well I don't know the precise what kind of valve it is but I have a diagram from another post on this forum. The valve that I made is a little bit diffrent.
http://www.spudfiles.com/forums/files/a ... ve_129.png
Greetings Tom

In my reasaerch what the best kind of valve's are, so I needed to make a valve that opens with the power of air. Making the valve was very simple and didn't cost me a day. I had some time left so i maked a rifle :D . I't dusn't look bad for a first rifle, the reloading is pump-action with a magazine...

I just maked a piston for a 32mm (1.25inch) pvc pipe, when I put pressure on the piston its leaking. I lubricated the piston but in won't help, dus somewhone now how to fix this problem.
Greetings Tom

It's a mixture of butane and propane.

Yes, the feul mixture will consist 3/4 air and 1/4 lichter fuel.

This is my first project in combustion cannons, the goal is to make a semi-automatic combustion cannon. The reloading of the ammo wil be with a gravity magazine, the feul injection will be injected thro the barrel with a piston. The schematics wil come... SOON .
Greetings Tom