If you don't mind me asking... What was the point of this topic?

I personally call it a syringe valve (and I think others have too) because your prototype was in a syringe and what you use for a piston is from a syringe...

It is a gun with a big chamber that leads to a regulator that leads to a smaller chamber which leads to a sprinkler valve and a barrel.

Co2... Go and buy a 20 oz. bottle and a regulator and your problem is solved. Soda bottles won't work, trust me. Co2 is a better investment if you are going to use the cannon a lot.

If you have such guns good for you, post them in this thread and we may change our minds slightly about you being a complete and utter moron. Do you have a 500psi bb gun to match mitchza89? How 'bout it, do you? If you do I'm sorry, but in all honesty its probably best not to challenge the 'veteran...

How about a soda can, even though it doesn't have as much of a cubic volume the overall cannon would look better. And it would be able to house more barrels. On top of everything else it would be cheaper to mass produce, if you want to. Oh, and having a lot of barrels isn't always best, because your...