The shoulder will, however, be pushed down the case (i.e. be bumped back), and those marks will end up one on the neck, and the other partway along the shoulder.
Reloaders take a short cut and explain everything is 'bump' as in the shoulder is bumped back etc. Many years ago there was an argument that involved Hatcher and his work. Hatcher was convinced a the case would suffer case head separation if the clearance was .060"+.
Hatcher added .060" to the length of the chamber from the shoulder of the chamber to the bolt face. and then fired minimum length/full length ammo in his new creation. During firing his cases did not suffer case head separation nor did they stretch between the case head and case body.
I said I have fired ammo in two of my rifles that had .127" clearance between the shoulder of the case and shoulder of the chamber, it was not a miracle but the case did not stretch between the case head and case body and the shoulder did not move. When I ejected the cases I found the case had increased in length from the shoulder to the cases head .127", I discovered the shoulder did not move, I discovered the new shoulder was formed from part of the neck and the increase in the case body was formed from part of the shoulder.
I understand the problem that goes on in the head of the reloader, it is not me, reloaders insist the case had head space, they insist they can bump the shoulder back, from the beginning I have suggested the reloader scribe the case body/shoulder juncture, I suggested scribing the case would have reduced Hatchers perception of what happened when he did not get case head stretch and or separation.
How did I get .125" clearance between the shoulder of the case and shoulder of the chamber? I fired 8MM57 ammo in an 8MM06 chamber. The difference on length from the shoulder to the case head between the 8mm57 and 8mm/06 is .127".
When firing and forming there are artifacts that are left on the case, rather than depend on artifacts I have scribed the cases as an example I find it convenient top scribe the case body/shoulder juncture.
I understand there are reloaders that are so desperate for attention they have no standards for behavior. MG has blamed me for his failure to understand. But if he understands ask him if the scribed mark at the case body/shoulder juncture did not become part of the case body when fired....why didn't it.
F. Guffey


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