1 Quick BBMG Question

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jwilson7
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Wed Apr 01, 2009 11:29 am

I was looking around and I found a post on this
topic that said
Co2 is a no no with pvc. Remake it with copper then you can use co2
I was just wondering if this is true.

Thanks,

jwilson7
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Wed Apr 01, 2009 11:34 am

It's true. CO2 supercools when it expands, and PVC gets very brittle at low tempurature. Not safe.
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jwilson7
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Wed Apr 01, 2009 11:50 am

But this wouldn't be true for a BBMG right?
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jimmy101
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Wed Apr 01, 2009 12:00 pm

jwilson7 wrote:But this wouldn't be true for a BBMG right?
Actually, a BBMG would be the worst case. You're dumping lots of CO2 through the gun when it fires and it'll freeze up pretty quick.

CO2 should be fine for a semi-auto or single shot setup. A metal expansion chamber will help warm up the CO2 before it is injected into the chamber.
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Wed Apr 01, 2009 12:55 pm

Haven't there been tons of regged CO2 bbmgs already? Ya know, like the "ultimate inline". BBMGs tend to run at low chamber pressures by nature.

I generally don't even worry about cold pvc since I use eye protection, but when frozen exploding cannons become an epidemic I'll be sure to watch out.
For now, I can't remember a single case of a cannon exploding from very low temperatures.
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jimmy101
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Wed Apr 01, 2009 2:04 pm

Plus, a BBMG is typically operating at 15~20 PSIG (even if the reg is set much higher, say 120 PSIG).

Everything is fine, though the gun might ice up. Only problem is, what happens if a round jams in the barrel?
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Wed Apr 01, 2009 3:59 pm

I would worry more about the potential high pressures of CO2 in PVC before I would the coldness of it.
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