Making my first cannon

[lemmiwinks]

I've been researching stuff for a while and I think I finally decided what I want to do, wondering if you guys had some input.

I'm going to make a pneumatic cannon with the premodded sprinkler valve off BCARMS. I'm thinking a 2" diameter, 5' barrel and a 3" diameter, 2.5' to 3' chamber, or a 6' barrel and 3' cahmber but I'm afraid this will be too bulky. I'm not looking to have an obscene amount of power or anything, my main goal is to shoot snowballs at my friends... For the winter, anyway, I'll be shooting different stuff come summer, so power is still good. So do you guys think this will work well? Any recommendations or anything? And I've already read all the safety stuff and everything, so I know all about PVC exploding and whatnot. Thanks for the help.

[ShowNoMercy]

my main goal is to shoot snowballs at my friends... For the winter

Umm thats kinda against most sane peoples rules about using PVC. But whatever, you

know all about PVC exploding and whatnot

[pat123]

If you are going for 6' barrel and 3' chamber I would make an over under because it woud be hard to hold a 9' gun. If you wantmore power you could make a piston valve. The rules say that you can't shoot stuff at people but snowballs are probably ok but be careful.

Discussion of shooting anything at any person and/or animal is prohibited, and may result in a permanent banning of your account.
The exception to this rule is for proper use of legal airsoft and/or paintball markers.

good luck and welcome to spudfiles

[Fnord]

A non-icy snowball fired from this cannon won't be lethal, but it will certainly hurt. A lot.

You should keep the pressure low to avoid inflicting bruises and reducing the chance that a sudden impact or drop will cause the chamber to rupture.

[lemmiwinks]

If you are going for 6' barrel and 3' chamber I would make an over under because it woud be hard to hold a 9' gun. If you wantmore power you could make a piston valve. The rules say that you can't shoot stuff at people but snowballs are probably ok but be careful.

Discussion of shooting anything at any person and/or animal is prohibited, and may result in a permanent banning of your account.
The exception to this rule is for proper use of legal airsoft and/or paintball markers.

good luck and welcome to spudfiles

Yeah I actually saw that in the rules, but i didn't see how a snowball could be any more dangerous than a paintball when fired at someone. I'm more worried about it being top heavy, but I guess I could make the chamber longer. The chamber volume is supposed to have a greater volume than the barrel, right? I could go with like a 4' chamber and 6' barrel...

my main goal is to shoot snowballs at my friends... For the winter

Umm thats kinda against most sane peoples rules about using PVC. But whatever, you

know all about PVC exploding and whatnot

Why is it OK for people to use these to shoot paintballs at people, but not snowballs? Or are you referring to the fact that I want to use it in the cold? (If you are, my plan isn't to keep it outside long enough that it can get cold and shatter)

[ShowNoMercy]

I meant for using it in the cold, PVC and cold are not good friends, but yea, I shoot paint balls at umm silhouettes all the time

[lemmiwinks]

A non-icy snowball fired from this cannon won't be lethal, but it will certainly hurt. A lot.

You should keep the pressure low to avoid inflicting bruises and reducing the chance that a sudden impact or drop will cause the chamber to rupture.

I was planning on using it at a distance, so it'll lose a lot of its energy by the time it hits someone. I don't know what pressure I'm going to operate it at, I'll figure that out after I build it, but I plan to keep it under 100 PSI.

[BigJon]

I think you're trying to make it way too big for what you are wanting. Maybe something like 2' of 3" for chamber and 4' of 2" barrel. That would make it a lot smaller and it will still have some power.

[SpudUke5]

Or you can just build a combustion if you want it for cold use. All you would have to do is use so wadding to make sure the snowball doesnt melt and then it should be good. Or you can make a small metal gun and shoot small snow balls at people. I just wouldnt trust pvc even at 80 psi i the winter and dont want to risk dropping it.

[pat123]

at 50 psi my gun will shoot a marble through a 1inch thick piece of plywood and it uses a modded sprinkler. I don't think i would shoot anything higher the 30psi or so at a person.

[ShowNoMercy]

Why not? No pain no gain.

[lemmiwinks]

So I was just thinking again, and now I'm considering having a 2.5" or 3" diameter barrel as well, maybe a 4' barrel and a 4' chamber to keep a decent ratio? Maybe if I just screwed the barrel in w/tape instead of gluing it so I could make a smaller barrel later if I wanted to. Is this a bad idea, will it hurt the power a lot? It just seems like 2" is a pretty small snowball. Would this work well?

Also, I'm trying to locate a schrader valve / gauge combo so I don't need to drill into it, for the sake of convenience in screwing everything in and for integrity of the PVC... Does anyone know where I might be able to find one? I've searched the forum and the internet with no luck, so any help would be appreciated. Thanks!

[ShowNoMercy]

I don't think they have schrader valves but they have pretty much everything else you may need. And its all relatively cheap. http://www.surpluscenter.com/air.asp?UI ... atname=air

[sjog]

http://www.spudfiles.com/forums/viewtop ... mage-7.jpg[/img]

[lemmiwinks]

This thing? Cool

http://shopping.msn.com/Prices/shp/?itemId=728685163

But why is their picture different from yours?

edit: actually looking at it again it is the same, just black and white and a different angle. stupid me. But one question, does their tire valve work with a standard bike pump? Thanks


edit2: THis should work the same way, right?

http://www.improvementdirect.com/index. ... D=99605470#