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“I think I should put a few words of caution in this thread about reduced loads. The .30-06 and other cartridges based on it are norious for shoulder set back when the firing pin smacks their primers and drives them hard into the chamber shoulder hard enough to set the shoulder back and increasing head clearance. Then the round fires and the primer backs out stopping against the bolt face. If there's not enough peak pressure to expand the case fully to the chamber wall and bolt face the primer will still be protruding from the case head and fired case headsapce is shorten that had a full pressure load been fired”
“I think I should put a few words of caution in this thread about reduced loads. The .30-06 and other cartridges based on it are norious for shoulder set back when the firing pin smacks.......”
Then:
“Same thing happens shooting a .308 Win. round in a .30-06 chamber. And there are other mismatches that'll do the same. Such is very normal when the extractor's holding the case head near the bolt face while the primer's struck by the firing pin. Nothing new about this at all”
Back to distinguishing fact from fiction and truth from nonsense, when applied to the 308 W fired in the 30/06, that is fiction, nonsense also applies, the case body/shoulder juncture is larger in diameter then the 30/06 chamber body at that juncture, meaning the 30/06 chamber reamer will not clean clean up the 308 W chamber, when a 308 W is chambered in the 30/06 chamber the case head spaces? on the case body/shoulder juncture. AND, when the 308 w is chambered in the 30/06 the the bolt sizes shoulder of the case.
“ I think I should put a few words of ......” You could consider adding a few words, the case, bullet and powder outrunning the firing pin defies the description of an accident. If you are using primers better described as King Kong primers there is a good reason for the case to run to the shoulder of the chamber, bracing, to bust the King Kong primers bracing is required.
In the perfect world the case body/shoulder juncture of the 308 W is .013” larger in diameter than the 30/06 case when measured the same distance from the head of the case.
“....for shoulder set back when the firing pin smacks their primers and drives them....” Then there was the protruding primer caused by low pressure, it is an assumption the case is driven by the firing pin, but as you said, “Nothing new about this at all”.
F. Guffey
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