gamestalker
member
I recently come into some new IMI .357 mag brass and am pretty puzzled right about now. Every 3rd or 4th case into the expander / belling die, the case will seize up in the die. I can fell as each round leading up to this event increases with resistance. So i took the expander apart and the plug had a lot of brass piled up on it. I cleaned it with some fine compound, took about 4 or 5 minutes to get it off, it came off very easily. Once again the brass was seizing up. Problem is getting worse when priming. The IMI brass will not accept a primer at all. The primers are getting mangled? JSmith had some similar problems with PMC brass?
So I decided to see what would happen with another case head, not IMI brass. I ran a large amount of mixed brass through resizing, belling, and priming, everything went off without a hitch and was normal.
Anyone have experience with IMI .357 mag brass. I've been loading the .357 for decades and have never had anything like this happen with brass, I'm stumped. This brass is definitely not in good spec. and at the very least I will need to do some primer pocket work to get them fired for the first time.
GS
So I decided to see what would happen with another case head, not IMI brass. I ran a large amount of mixed brass through resizing, belling, and priming, everything went off without a hitch and was normal.
Anyone have experience with IMI .357 mag brass. I've been loading the .357 for decades and have never had anything like this happen with brass, I'm stumped. This brass is definitely not in good spec. and at the very least I will need to do some primer pocket work to get them fired for the first time.
GS
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