Thanks to everyone for the kind words. Boredom and hint of insanity can create some cool stuff.

Heres more pics. The pressure gauge is brass it came from a different extinguisher it is sprung from overpressure, new gauge on the way not brass though. http://i284.photobucket.com/albums/ll33/crashdaddio/100_2851.jpg
http://i284.photobucket.com/albums/ll33/crashdaddio/100_2855.jpg
http://i284 ...

I was kinda going for "Terminator" meets "20,000 leagues under the sea"

Thanks for the props this cannon was just finished just before my neck surgery. The only thing that has been down the barrel so far has been a couple of wire nuts. I will post the pics asap It put a wire nut through 3/4" ply @ 300psi most of the way through a 3/4" laminate counter top.

Ive had it up to 400 psi it ruined the present gauge. The chamber has been tested to 550 psi.

This is the newest of a number of cannons over the years. It is a barrel sealing piston valve in a 1" tee. 1/2" barrel,aluminum FE for chamber, much modified sandblast gun for the pilot. the stock was made from scrap aluminum from other projects. Milled by hand with the help of a drill press, rotary ...