What I have right now?

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
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DYI
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Wed Sep 05, 2007 6:19 pm

I think that you should take into consideration what will happen to the PVC barrel when exposed to a pressure spike of almost 800 psi.

And what do you mean by "On/Off will work as the valve"?
Orpackrat
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Wed Sep 05, 2007 7:20 pm

DYI wrote:I think that you should take into consideration what will happen to the PVC barrel when exposed to a pressure spike of almost 800 psi.

And what do you mean by "On/Off will work as the valve"?
The PVC will be fine unless he seals the barrel somehow and the Co2 has no where to go.

An on/off valve on the ASA. Basicaly it is a duel valve launcher, the first valve is at the tank, it fills the expansion chamber with Co2 and is then shut off to disconnect. The second valve empties the expansion chamber and fires the launcher. With the second valve at the tank and it being shut off after the chamber is filled, there is no wasting of Co2 from having the firing valve left open.
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sniperx117
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Wed Sep 05, 2007 9:14 pm

DYI wrote:I think that you should take into consideration what will happen to the PVC barrel when exposed to a pressure spike of almost 800 psi.

And what do you mean by "On/Off will work as the valve"?
By the time I open the valve all the way, there wont be enough pressure to assplode teh pvc p1p3
nivekatoz
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Fri Sep 21, 2007 7:55 pm

silicone seleant on the threads works good...
use alot of it and let it cure or dry...it takes time but it works good ,really good.....
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DYI
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Fri Sep 21, 2007 8:23 pm

People have blown up PVC barrels before with 7 and 8x hybrid mixes, which are roughly equivalent to 800 psi, and those were pressure rated SCH 40 barrels. Even with the movement of the projectile and a slow valve taken into account, there will still be a short pressure spike which could reach a peak of at least 500 psi, if not more. I'm not saying that it will definitely explode your barrel, but exploding PVC is very unpleasant and sharp, and it only has to happen once.

Why couldn't you just use copper or ABS for the barrel? Copper should survive easily, and with ABS, even if it didn't survive, you wouldn't have really lost anything. I've never had a (solid wall) ABS barrel explode, and I've put a lot of stress on some of them (i.e. Oxy-MAPP mixes, 500 psi pneumatics, etc...)
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