SpudFiles

Yea thats basically how it works but it actually leaks through the sides of the piston rather than just straight down. T=you also want the barrel to pertrude into the T so it can get a better seal on the barrel.

but essentially what you hae i correct, just not to scale. You just wanna keep that pilot volume small and you can get the best performance out of your cannon.

when ever i try to make a piston, it wont move inside of the T to form a seal against the barrel, air will leak past it, but because it dosent move the piston it wont seal.

Currently im useing a 1/2" bit of abs pipe with a rubber tap seal thing on it to form the seal.

How much space do people usually leave between the piston and the T that it is housed in? Also what would people suggest to use as thea piston?