Here is what I found on measuring cases and rounds.
Trim length was 1.750 on all the brass after sizing.
One fired round that cycled fine:
1.745 brass length
.311 from mouth of case to just below shoulder where cs flattens
.356 dia. at top of shoulder just below the neck
.170 neck length
One loaded round that jammed:
1.740 brass length
dia. at top of shoulder .358 (where it looks like bulge)
.187 neck length
.309 from mouth of case to just below shoulder where cs flattens
One loaded round that wasn't in the mag:
1.737 brass length
dia. top of shoulder .368 where it looks like bulge
.184 neck length
checked Several cs not loaded:
1.750 brass length
dia. at top of shoulder varied from .354- .368
.184 neck length consistently
Since the SAMMI standards show .3542 just below shoulder where cs flattens- mine are all bigger, especially the one that jammed as well as the one that wasn't in the mag and is unfired.
I think this must be from the resizing step or maybe the seating step. When I get the case gauge that I ordered in the mail, I will set up the dies using that hopefully that will cure this problem.
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