What is proof pressue? About 6 mounths ago I had asked the differance between CUP and PSI, now where might this term fit in to everything.

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Just for info if interested-
We had to proof load (testfire) every barrel we manufactured for our guns with special "proof ammunition" and then have them mag-particle inspected etc. afterward to look for any possible cracks/failure modes. Proof ammunition since not mass-produced is more expensive, and basically a "hand-load" to specific specs from the ammo manufacturers.
Most countries only required the barrel to be validated, but some like the UK could be a real pain. They required the barrel, breech, bolt, and muzzle-break all be "proofed" together and per different(higher pressures) requirements than normally done; as well as have their own "Proof Masters" witness the event (usually). (They have their own proof markings as well to apply) This basically meant total assemby of a gun, fire one round, then disassemble to get parts inspected, then reassemble again afterwards. (expensive process)
Some ammunition would/could also be heated to certain temperatures in an oven to increase the pressures if required in some testing.

Unit5A-

WHere were you working making those rifles? Any idea what the proof pressure was? Who did you get to make it for you? Were you magging the barrelled action as an assembly after the proof load?

Sounded like you had some interesting experiences there and I was just curoious.

Thanks!

quote:

Originally posted by Marc_Stokeld:
Unit5A-

WHere were you working making those rifles? Any idea what the proof pressure was? Who did you get to make it for you? Were you magging the barrelled action as an assembly after the proof load?

Sounded like you had some interesting experiences there and I was just curoious.

Thanks!

I was in the Ordnance business for over 25 years until recently in both Calif. and here in AZ, primarily manufacturing medium caliber guns/automatic cannons and barrels for military usage, both US and foreign; but got to play with all kinds of neat stuff and enjoyed the heck out of it most of the time...the playing part that is, ha ha. After 9/11 for example, an airplane company paid us to try and shoot through all kinds of cockpit doors to see if the new designs would stop a terrorist using all kinds of calibers/guns/loads. So we got to play with a lot of stuff we didn't even make ourselves, because we had good testing facilities and equipment. Then of course, trying to shoot up old M113 vehicles, aircraft wings, and other stuff in the desert was always cool too for demonstrations to customers. Interesting work for sure.
Anyway, after "proof" the parts have to be "magged" separately or a crack could be hidden/missed, and depending on materials used could be penetrant inspected instead. Again, in most cases it is only the barrel alone requiring a proof and then mag inspect. Barrels are usually proof tested in a special fixture in economical lots by the way, and not in an actual gun. I don't remember all the different pressures for everything, and all are driven by specifications set by military/gov't(?) etc.; I would have to look all that up.
Most ammunition today made in the US is from ATK, or what was General Dynamics (GDOT? I think its called something else now, not sure), but that is where we would get it from usually, if not supplied by the government themselves on a contract. Everybody keeps buying each other out so often, parent companies etc., it is hard to keep up with who's what anymore.
Take care.