This is my first time working with metal, so i decided not to try anything innovative or new, just a plain ol' piston valve housed in a tee. There were no modifications to the fitting, just normal threaded pieces. It wasn't a planned project, i just had a tee and a hosebarb originally, the rest was bought for about 30$.
I haven't fitted a barrel on yet, nor have i taken it past 160 psi, so i don't know its full potential, but it sure makes a great noise.
I also tried for minimal parts on this cannon due to budget issues, so i pilot and fill through the same valve
Here's Some Pics
Piston:

Full Gun:

Watch this space for updates Including a barrel, damage pics and more










