How much pressure

[Kaiser Bill]

You could go for abs as it could split but not turn in to shrapnel.

[ProfessorAmadeus]

NO PLEASE DONT DO THAT!! That would be a very bad idea. ABS i think someone olny pressure tested to 69 psi or something like that. PVC has large safety margins on it but i dont think it necissary to take your gun to 300PSI.

[carlbelcher]

ProfessorAmadeus is right (partially) don't use ABS it is not pressure rated or tested to even 2psi let alone 69psi.

[boonedog132]

guys guys dont worry i went to bought pipe that is pressure rated to 280psi and i cut some custom bullets outta wood they work SOO AWESOME

[ProfessorAmadeus]

http://www.spudfiles.com/forums/viewtopic.php?t=2956& looky there

[carlbelcher]

I really don't care if someone has "tested" ABS pipe. The point is the pipe he tested might have blown at 69psi but the pipe that you or I get may blow at 25psi or 1000psi... you just don't know. They don't test the pipe for pressure at the factory so the actual bust pressure will undoubtly vary by manufacturer or even by batch of pipe. Since they don't have to worry about making sure the pipe doesn't burst bellow a certain pressure they won't.

[Flinchy]

you want to be careful when you start using ABS plastics. i've heard many rumors about ABS, about them being harder, able to hold more pressure, and so on and so on. but no matter what pipe your using its only a matter of time until it begins to fracture. remember, nothing can last forever, however some things last longer than others, such as metal pipe. if you keep pressurizing a PVC chamber, you never know when the pipe has had it, this is why you look the cannon over for stress marks and creases. you may be able to get 500 shots off with your cannon before it fractures, or you could get around 5 *memorie of friends cannon*. either way you just never know.

-flinch

[theRIAA]

lol, your freaking him out.

just do what I do, put the gun and air compressor on one side of your house, let it charge to like 200 psi and then toss a big hammer at the tank (while standing around the corner) if it explodes then dont do that again, if not, you're safe to use it at 150psi (my maximum psi for ABS under 2" and a sprinkler valve)

[super spuder]

that sounds real safe

[integral]

lol, your freaking him out.

just do what I do, put the gun and air compressor on one side of your house, let it charge to like 200 psi and then toss a big hammer at the tank (while standing around the corner) if it explodes then dont do that again, if not, you're safe to use it at 150psi (my maximum psi for ABS under 2" and a sprinkler valve)

hahahahaa! That has got to be more stupid than sticking your tongue down the barrel...

[jimmy101]

Look closely at the end of the pipe. Does it look like solid plastic? Or, does it look a little like foam, with lots of very small pin holes, or any other indication that it is basically frozen foam?

Does the pipe say anything on it? If so, what exactly does it say?

Call the store and ask'm what kind of pipe it is. If they say it is "cell core" or "cellular core" then you should probably take a sledge hammer and smash the gun into little pieces. (If you do call or visit the store make sure you talk to someone that knows their ass from a hole in the ground!) Or, glue the ball-valve open and convert it to a combustion gun.

"I really dont understand why you put all these fancy valves in your guns... buy the 12 dollar pvc ball valve it works perfect"
No it doesn't "work perfect", it just works and was easy and fairly cheap to build. A better valve will significantly improve the performance of a gun. To get the most out of a compressed air gun you need to be able to open the valve in significantly less time than it takes the spud to transit the barrel. For a muzzle velocity of 500 FPS and a 5' barrel it takes ~0.02 seconds for the spud to transit the barrel. Can you open the valve in less than 0.02 seconds? (I would think that perhaps ~0.1 seconds would be the best you can do by hand.)