The discussion and the link are interesting and shed further light into the dark corners. The description of the breech face battering around the firing pin hole is especially interesting and VERY revealing, at least to me it is.
The description of the battering is identical to the battering caused by initial excessive headspace.
The firing pin strikes the primer and simultaneously indents it & drives the entire case forward against its shoulder, as far forward as the chamber will permit. The priming compound ignites, driving the primer (but not the case) back against the breech face. This is where the battering begins, with the running start imparted to the primer. The powder then ignites and may or may not drive the case head back against the breech face. If the case DOES drive back against the breech face, the battering becomes much worse.
I posit that the '03 & '06 examples were afflicted with loose chambers and maximum headspace, as already recounted. I further posit that repeated firings would first cause and then exacerbate an even worse excessive-headspace condition.
As circumstantial but compelling supporting evidence I cite the extreme LACK of negative reports on the rifles chambered for the 7.62 Russian cartridge. The dog that did not bark in the night if you will. This cartridge has MUCH LESS capacity than the 30-06 but yet produces velocities that almost always equal or exceed the '06. Obviously, very obviously, the Russian cartridge must have been loaded to even higher pressures than the '06 so why didn't THOSE 1895s get the bad rep?
Ah, you say, but the Russian cartridge has a larger rimmed footprint and so would exert less pressure per square inch on the breech face. Oh, I say, but the primers are exactly the same size and so the smaller-diameter battering as previously described should still have occurred, but apparently did not! Therefore I conclude that pressure, per se, was not the prime cause of the '03 & '06 problems.
So therefore I return to my initial analysis and recommendation of taking extra care in the headspace determination. If pressure and old steel was really the problem then I should have noticed this about 40 years ago when I began working with early Win 1885 single shots and modern hot cartridges. NO SIGN of battering in any of my walls but then again all are chambered to minimum headspace. JMOFWIW.
Regards, Joe
