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Sizing die question

MT257

Well-Known Member
Joined
Aug 26, 2015
Messages
523
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MT
So I am full length sizing some brass. I ran it through my die and they come out looking like this. Should I be concerned about the line above the belt? Do I have my die set incorrectly? Is this how old brass gets? I'd say this stuff is nearing the end of its life.
IMG_8108.jpeg
IMG_8107.jpeg
 
Since no one ever said anything.

It's normal, northing to worry about. The die isn't going to size down to the top of the belt, but that shouldn't be an issue because while the belt covers the web of the case the walls are still pretty thick that far down and shouldn't expand to the point of a chambering problem unless you really push the pressure.

On the off chance you do have chambering issues from it there is a special collet sizing die to resize the specific area of the case.

Sectioned 300 WM case showing the belt in relation to the web:
Gunwerks-300WM-Brass-Cross-Section.jpg
 
Like QT said. Many years ago I had a 7mmRM and after about 4 firings the rounds got progressively tight when closing the bolt. This was from expansion just in front of the belt. The Willis die was around then or I just didnt know about it but would have fixed the problem. Chose never to own another belted case. Sinilar to neck sizing only where after repeated firing the case gets to tight and has to be full length sized or replaced.
 
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