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drill702

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Hello all , I picked up a post 64 model 70 in 264 and noticed the brass on the once fired factory ammunition has stretch marks above the belt . Got to comparing factory ammo and the once fired and see what I believe to be a substantial difference. What do you all think?
 

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Part of the problem is all standard magnum belted brass is made under size... smaller than saami specs call for...

Ignore how your brass looks and continue shooting...

if you are reloading, don't push the shoulder back on the once fired brass when sizing... use the shoulder to head space on, not the belt.
 
And it might be an idea to treat the cases as rimless when sizing. This should reduce how much the brass gets worked.
 
All of the above.

It's also been my experience that the magnum pressures/heat cause the cases to harden sooner, making them harder to resize, even with just neck resizing.

You can't just keep neck resizing, eventually you will have to bump back the shoulder and that will likely include having to soften/re anneal the neck and shoulder area. .
 
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My Pac-nor .264 W.M. allows for quite a bulge above the belt too. Standard resizing dies will not reduce this area enough to easily chamber more than once fired. I just got a Larry Willis Belted magnum collet resizing die, it works great. It only resizes the area above the belt.
 
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