SpudFiles

Since I'm having trouble finding a good sealing surface for my piston, I was wondering if just putting the half of the union with the rubber ring on the end of my barrel. This way, I could use any piston with a flat end without having to worry about adding a seal to it every time I make a new piston or switch pistons.

I can get 3/4" Unions for under a dollar so I figure, I might as well use it.

Another thing, would a 3/4" Union fit in a 1.5" Tee? Or would I have to trim it up?

Well, when i was picking parts for my cannon, i had a few of the hardware store workers kinda stired up because they could not understand why a irragation system was in need of so many odd parts. Plus i kept conpairing fittings to the pipe on the shelf. Talk about getting a bunch of looks. So just go to the hardware store and start eyeing up parts, thats how i did it.

That's not even related to his question.

Yes, it should work but I'd be worried about the piston aligning to it right every time. I'd just make a barrel sealing tee valve in a 2" tee. Those work very well.

If you don't feel confident in that I'd be happy to sell you one. My 1.5" porting "Shredder" valves are complete. But if you wait a little longer I'll have my 2" porting "Mauler" valves done. They should be fully tested in a couple weeks.