Hey there,
Those "file marks" at the case mouth I get those too on my Glock 22.
Just a remark the amount of crimp you're using could be excessive in addition to the comments about the powder choice being too fast.
SAAMI specified maximum = .423
Tightest I've seen suggested = .421
From what I've read elsewhere I think a slower powder might be the answer though.
Safe shooting all
|