Safety Question

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Ballad_Black
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Tue Apr 11, 2006 11:55 pm

Hmm. As a few of you might have noted, I havent been around much lately. In fact, I had'nt made a new gun in a month or so. Well, today I went AWOL at Lowe's with my pay check. I had the fever.

Now, my chambers are usually 3 inch Pressure rated Sch 40, but today the 4 inch pipe was calling. In my blind fury to grab pipe, fittings, etc...I negated to look at the 4 inch pipe's rating. Assuming it was pressure rated and Sch 40, I ran home and brandished the saw. Cut myself off 10 inches and began the priming and glueing.

It was'nt until the chamber was finished that I saw it. Sch 40, yes, then ***NON PRESSURE RATED*** was printed on the pipe. Now, I've been out of the ring for a while and this worried me. I started seraching around the site and found a few threads which made me feel better.

This cannon is going to have Propane injection via a schrader valve, and it's non pressure rated Sch 40. Im thinking I will be fine, but a post form Pimpmann, BLB, or Spudshot will settle my nerves.
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boilingleadbath
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Wed Apr 12, 2006 12:22 am

It most likely won't blow up, bu I didn't tell you that.

For example, there have been many combustions built with cell-core (more if you include ABS), and at least 2 pneumatics that I know of... no failures that I heard of.

Taking a computational route, 4" solid core is rated to 220 and the solid portion of that pipe typicaly looks to be ~1/3 of the thickness, so I'd say it'd be rated to ~70.

...but remember, I didn't tell you that. For liability reasons.
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Ballad_Black
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Wed Apr 12, 2006 12:27 am

Hmm, I thought it was in that ball park, and to another question. When the explosion happens in the chamber that causes the projectile to be shot out, is'nt it around 50 psi? Or did I just dream that somewhere...
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boilingleadbath
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Wed Apr 12, 2006 11:22 pm

30-50 PSI, depending appon who you ask.
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alex bennett
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Fri Apr 14, 2006 12:12 am

As long as your projectile isnt shoved so tight that it cant get out, you shoud be okay. This is from experience, i shoved a projectile really tight in my barrel, and when it combusted it threw the end cap back about 15', broke my seals on the reducer (on both sides, the chamber and barrel)

Scared the s#@% outta me, now i make sure my projectiles can leave the barrel with minimal resisance. The chamber held up...in my case im pretty sure others have not been so fortunate.
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Ballad_Black
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Fri Apr 14, 2006 2:53 am

Yea, I have a scar on my wrist from an end cap being shot off. I's a perfect 90 degree half square. Been there since my first gun, so about 6 months old and still shining.

As for projectiles, potatos and maybe some wax slugs. Nothing too tight to where you cant push it out with a ram rod.

Also, I've heard Cell Core is extremely bad. Which is what my chamber is. Can someone tell me why this is so? Outside the fact it doesnt have a pressure rating.
It's plenty strong and can take an ass whippin. I had an old chamber from a past gun I used for parts, took it out to a dumpster, and beat the hell out of it. It would'nt budge until the endcap crack and took the chamber with it.

Sorry I keep going on with this, I just don't want all the cash I spent to goto shit.
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