How many PSI can brass 1/4" and 1/8" fittings take

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c19o
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Fri Jan 26, 2007 11:29 pm

How many PSI can brass 1/4" and 1/8" fittings take? and also steel or galvanized steel fittings. I asked alot of people and they didn't know. I also googled it and didn't find much except this one place that said they will go up to 150 psi. The reason for this is that im making a bolt action or semi automatic ( if i can figure out how) marble gun and i'm going to run onboard co2 at, at least 150 psi. And Im also goin to make a high pressure cloud bb mg that shoots the regular metal bbs.
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judgment_arms
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Fri Jan 26, 2007 11:53 pm

Don’t know about the fittings and pipe but as for a semi-automatic marble gun Google “Boltsniper” (this is about the fifth time I’ve told someone to do that this week.) he made a semi, or was it fully automatic NERF gun that ran on Co2. Also, if you got a lot of money, get a cheap Tippmann 98c and take it apart and learn how it works, or just find a blow apart/schematics of paintball guns and go off them.

Been meaning to ask this and now’s a good time: what if you placed a magnet at the breach of the barrel of a cloud to put more resistance in the system so the pressure goes up more before “firing”. Would it help, and did I make my self clear enough (I’m tired so I probably didn’t.)?
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frankrede
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Sat Jan 27, 2007 12:17 am

Those fittings can be trusted up to over 250 psi.
It depends on the fitting though, I have seen Precision-Machined Yellow Brass fittings with a 3000 psi rating.
Don't worry about it your measly 150 psi won't make your fittings fail.
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MrCrowley
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Sat Jan 27, 2007 4:36 am

Unless you use co2 for filling I guarantee you the threads will leak first,before it blows up. It should be safe 250-300psi but like I said the threads will start to leak,Its hard enough getting a good seal with teflon at 150psi.
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mark.f
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Sat Jan 27, 2007 8:17 am

I don't know about you guys, but a common rating I've seen on brass is 1,200 PSI. Look on the specs if you're ordering the fittings and ask the guy at the store what the pressure rating is if you're buying it from a store.
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c19o
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Fri Feb 02, 2007 11:32 am

Thanks for the help guys. I'm going to keep looking some high pressure rated fittings (about 500 or more psi).
Hawkeye
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Sat Feb 03, 2007 1:35 pm

They can definitely handle high pressure. I think a brass schrader can take 500 psi. I routinely use small brass fittings for my copper guns and take them well over 200 psi. Most brass fittings for pneumatic tools have a high rating as well. They don't leak either. If they do, you're not putting the thread sealant on properly or the thread quality is poor.
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Hotwired
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Sat Feb 03, 2007 4:20 pm

You'd need godawfully high pressure to cause pressure line fittings to burst.

I'm using 1/4" fittings intended for compressed air systems and they're being run at 160psi (or a bit more if I overpump). I'm later going to increase that to 200 for normal firing and later, 300psi once I get hold of the right pump.

I believe you'd be looking at scuba tank pressure+ to rupture a metal fitting.

The nylon versions of the fittings I'm using have a 20bar working pressure, it doesn't even say how what the brass ones are rated to.
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