Thanks guys for helping me. But one more thing, what is the right pipe to use for the barrel of my marble shooter?

Far out .. i thought 50 was like piss week lol. the chamber i am planning to use will be made out of about a 2 inch round PVC pipe. and the barrel will be about...... 19 inch what do you think about that?

Lol. If they come round i will be like yer i only pump it up to 50psi. How far do you think that it would shoot? would it be powerful?

Haha. I'm back to making a marble shooter now. Would 120 psi be good for a marble? or should i make it so it can handle a higher pressure? Would this gun pass Australian regulations without having to have a gun license? Has any one else made a marble gun like mine? With the ball valve and things?

Very well done. and is that 933.3 miles per second?

THAT IS AWESOME. it has looaddddsss of power good job matee

Do you think i should give it hop up?

ok so round ammo would not work very good. so i am back to making just a marble shooter. thanks anyway guys.

soo jimmy101 what sort of valve do you suggest ? and i would have the right sized barrel for the ammo because i would drill a hole through the dowel and the small pipe the right size for the ammo would go in.
and whats the stick?

Hey guys, I'm planning on making an air pressure cannon that shoots the led balls out of shotgun shells. I'm going to get a normal sized barrel that screws strait into the ball valve and put a piece of dowel the right size into the barrel. I am going to get some really small metal pipe from the hobb...