I like to outside neck turn all my virgin brass, try to get things even. My question is my virgin rem brass is .012-.014 what would be the minimum thickness I could safely go?
It is 7STW. Thanks, Kasey1
It depends on what chamber you have in your rifle.
Are you using a factory chamber?
If so you should only turn off enough to clean up around 80% of the diameter of the necks. The general intent is to make all necks the same thickness to cause similar neck tension and release. To take off more than this with a "sloppy" factory neck dimension will cause the necks to prematurely a split do to work hardening.
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Is it a custom chamber?
Did a gunsmith use a reamer with a "no turn neck" size? If so it will have much tighter dimensions and you should be able to turn off enough metal for a 100% cleaned up neck.
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Or do you have a tight neck chamber dimension which requires you turn the necks?
The neck must be turned to allow the brass to fit. A specified dimension requires necks should be turned with at least a .0015" clearance on each side for bullet release or for hunting at least .002-.003" and in some instances .004 per side is recommended.