AR10 neck tension

If you are using a standard die/expander(they are usually 0.002 smaller than bullet diameter) decapping pin, all should be fine. Just double check to make sure you're not crimping during the seating process. Because of spring back I usually, load/seat bullets soon after setting the inside neck diameter. I use a Lee fcd for gas guns also, just enough crimp to prevent bullet movement when loading from the magazine. That is probably best checked outside at a safe location, no proud primers, safe muzzle direction.
 
Relentless2013 said:
I completely understand what you mean, I am just asking what neck tension most people are using before crimping. Thanks bud appreciate your help!
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I could be wrong but I see zero reason to worry about using a bushing die if your going to crimp, on my AR10 loads I simply run a regular full length sizer and ensure I'm bumping the shoulder 3-5 thousand then run it in the FDC die. Never had a single issue and get a lot of firings, the primer pocket usually goes first.

I anneal every firing so I'm not concerned with overworking the brass as much.
 
I dont measure neck tension and just turn the lee collet factory crimp die down a quarter turn after flush on my 243 AR rounds. Just a super light crimp. I also tried the small base die in both my 243 uppers vs the regular size FLS dies. The regular FLS dies i get get tighter groups when testing both sized cases with my pet load. I also anneal every other to three firings. I dont measure neck tension. Just full length size and a "light" lee factory collet crimp on them. IMO the necks always seem tight enough without a crimp but i like the piece of mind with a light crimp on them.
 
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