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James K · December 27, 2009, 08:29 PM

Late model 1893 rifles had a gas escape port drilled in the left side of the receiver ring, and some early ones were retrofitted. It is large enough to deal with primer leak, but not large enough to deal with a complete case head failure.

I have never seen a 93 Mauser "blow up" from using cartridges of the .308 class. But they are soft and not made for that pressure level; eventually the bolt lugs and the lug seats in the receiver will batter and create an excess headspace condition. You don't need GO/NO-GO gauges, only a field reject gauge. Depending on your loads, a check every 100 rounds would probably be a good idea. Also check your fired cases for any sign of stretching, like a bright ring around the case about 1/4" up from the base. If you see anything like that, stop firing the rifle immediately, like NOW. It is dangerous.

I think a bolt shearing its lugs is extremely unlikely; I have never heard of such a thing except in an American rifle, the M1903 Springfield when single heat treated bolts failed.

Here is something to think about. Imagine that the rifle is standing on its butt with the barrel pointing straight up. Now imagine a steel rod running down inside the barrel and on top of the rod is a platform. Every so often, a crane picks up a Ford 150 Super Cab pickup and drops it on the platform. That is about the pressure those bolt lugs have to stand up to every time the rifle is fired.

So, don't minimize the effects of rifle pressures.

Jim

December 27, 2009, 08:29 PM	#9
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Late model 1893 rifles had a gas escape port drilled in the left side of the receiver ring, and some early ones were retrofitted. It is large enough to deal with primer leak, but not large enough to deal with a complete case head failure. I have never seen a 93 Mauser "blow up" from using cartridges of the .308 class. But they are soft and not made for that pressure level; eventually the bolt lugs and the lug seats in the receiver will batter and create an excess headspace condition. You don't need GO/NO-GO gauges, only a field reject gauge. Depending on your loads, a check every 100 rounds would probably be a good idea. Also check your fired cases for any sign of stretching, like a bright ring around the case about 1/4" up from the base. If you see anything like that, stop firing the rifle immediately, like NOW. It is dangerous. I think a bolt shearing its lugs is extremely unlikely; I have never heard of such a thing except in an American rifle, the M1903 Springfield when single heat treated bolts failed. Here is something to think about. Imagine that the rifle is standing on its butt with the barrel pointing straight up. Now imagine a steel rod running down inside the barrel and on top of the rod is a platform. Every so often, a crane picks up a Ford 150 Super Cab pickup and drops it on the platform. That is about the pressure those bolt lugs have to stand up to every time the rifle is fired. So, don't minimize the effects of rifle pressures. Jim