Fireforming & resizing question

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lineofsight

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From what I understand, if fireformed case, dont full length resize, defeats purpose of fireforming, just check that case length within spec (and if need to trim then trim to short end so can grow), and check for overpressure & case wear. Reasonable?

So... if have a resizing & decapping die... turn decapper further out so can decap without pushing die onto neck & shoulder?
 
Yep, or you can buy a neck sizing die.

If you want to adjust a FL die out, one trick is to first remove the decapping pin, and then place a dime on top of the shell holder when you adjust the die down. This add'l distance has (for me anyway) always worked to size just the body and neck, but not touch the shoulders.
 
That would be partial full length sizing. Sometimes it works, sometimes it doesn't. WSM's will often buck this method.

If your full length sizing die is considerably smaller in diameter than your brass, the brass will still get squeezed in and can increase in length. If it doesn't spring back, depending on the size difference and hardness, the shoulder will move forwards and yo uwill have to bump it.

FWIW, many TOP level BR shooter full length resize every time, of course their dies are well matched to their chamber usually.
 
My father shoots a 22-250 Tight Neck with 1/2 thou clearance on each side.

He only has to deprime then prime, powder and bullet, no sizing requiered. About every 5 reloads he needs to "bump" the shoulder back and he is set to go for another 5 reloads.
 
Thanks for the comments. Will measure too and see what the differences are between the fireformed and full length resized. I just thought point of fireforming was perfect fit so sizing afterwards would be counter productive, problem is decapper is part of sizer...
 
Most FL sizers are designed to be on the small side of SAAMI spec. Otherwise, they wouldn't do much.

That oversizing will shorten brass life considerably but ensures smooth chambering.

The best way is to get a body die and just bump the shoulder enough to chamber. The base rarely grows unless you have a real problem with the lock up on your action.

So neck size then bump the shoulder as needed.

I am not a fan of partial FL sizing as it can lead to donuts forming on the neck. That will lead to poor chambering and other problems in bullet seating.

Jerry
 
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