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2'' air chamber

Posted: Thu May 17, 2007 12:15 am
by roughboy
Hey guys im building a pneumatic gun the air chamber is galvanized steel
2''x 12'' so, how much pressure can it hold? :twisted: thanks!

Posted: Thu May 17, 2007 12:25 am
by Orpackrat
I have only used up to 1" steel pipe from the hardware store and it handles at least 800 PSI. I use it in my Co2 (no regulator) launcher. What size barrel are you using, what length, and what kind of valve. I have a launcher with a chamber about 1/3 the capacity, it will fire a 8oz paintball grenade 150 yards easy.

Posted: Thu May 17, 2007 12:51 am
by roughboy
-barrel is 5' and it's 3/8''od copper
-the valve is a modded sprinkler valve
it is a coaxle piston gun

Posted: Thu May 17, 2007 1:01 am
by Orpackrat
In that case, i dont think a sprinkler valve would handle the kind of pressure I use, the highest pressure valve I have seen was 210 PSI max, My laucher uses an 18" barrel 2" dia with a 1" ball valve (because of high pressure. If I was building it, I would build it to accept high pressure Co2 and a ball valve for fun with high pressure and able to accept the sprinkler valve and compressed air for normal shooting, but thats just what I would do. Have Fun.

Posted: Thu May 17, 2007 1:12 am
by roughboy
so how much psi/pressure should i put in the gun. thanks!

Posted: Thu May 17, 2007 1:14 am
by MrCrowley
Depends on the pressure rating of the pipe. Do you know anything about the pipe? Any writing or do you know what schedule it is?

Posted: Thu May 17, 2007 1:17 am
by roughboy
No writings.

it's a all galvanized steel pipe 2''x 12''.

Posted: Thu May 17, 2007 5:54 am
by ShowNoMercy
But until you get rid of the sprinkler valve it does not matter what the chamber is made of. The valve is your weak link in the chain and cannot keep up with pressure of the chamber. Just get some PVC and make a regular cannon or get a ball valve rated for high pressure.

Posted: Thu May 17, 2007 5:56 am
by spudthug
or make a piston valve....

Posted: Thu May 17, 2007 5:59 am
by ShowNoMercy
How would making a piston valve solve his problem? Would he still be using high pressure?

Posted: Thu May 17, 2007 6:09 am
by chaos
could ya give us a wall thickness on the gal pipe?

i have seen piston valves used in excess of 400psi so my guess is use/make one of them.

Posted: Thu May 17, 2007 6:14 am
by ShowNoMercy
I did not know that you could make a high pressure piston valve. My bad

Posted: Fri May 18, 2007 12:54 am
by roughboy
what if i only use 130psi could my 1'' sprinkler valve handle that kind of pressure or should i lower the psi to 110psi?
by the way the gun im building is a piston gun,and the modded sprinkler valve/blowgun is the trigger. oh yeah the gun is all metal (galvanized)

thanks!! :twisted:

Posted: Fri May 18, 2007 3:27 am
by chaos
so what is the maximum pressure you want to use? coz a sprinkler by itself would handle 160psi alone

Posted: Fri May 18, 2007 3:56 am
by TwitchTheAussie
Geez go with a 1" Ball valve easy to operate and lots of pressure can be applied :P