Need advice, neck sizing

[dsass]

Hey everyone, first post here.
I'm getting back into reloading, haven't done it in a few years. I have hundreds of .308 cases from a few different manufacturers. All are once fired factory ammo. All fired from the same rifle. Can I safely neck-size all cases if reloading, or do I need to full-length size for uniformity for their first reloading? I figure all cases are fire formed to the rifle, just by different recipes of bullets and powder. The first few batches aren't meant to be match grade, just some quality plinking ammo. What do you think?

 

[Red Cent]

Neck size. Bolt action.

 

[Maj Dad]

First, sort it by maker, and lot # if possible. If it was fired in your non-autoloading (i.e., bolt action) rifle in which you are going to use the reloaded rounds, yes, you may neck size. If no, then full-length sizing is necessary, and if it was fired in an autoloader, small-base MAY be necessary, but not absolutely. I small-base size any 7.62 GI brass I get to avoid the machine-gun over-sized chamber issues, and also if I am not sure if it was fired in bolt gun. Having said all this, brass that I fire in my M14 semi with a GI chrome-lined SAK bbl works fine using a standard sizer die. Like they say, YMMV... I neck size to extend brass life, not necessarily for accuracy: the two don't go hand in hand. If you neck size & accuracy is mediocre or not what you expect, try full-length & see how that goes. It's the old trial and error and load work-up thing.

 

[dsass]

Thanks for the help.

 

[Slamfire]

Maj Dad has it right

At some reload point you will have to full length resize. I have read too many posts from guys who found that neck sized cases grew and they had trouble closing the bolt.

Check your case trim length. Don't want the case neck pinched in the throat.

 

[fguffey]

I can keep up with more than one thought at a time, I have neck sizer dies, they are nice, not necessary, just nice and when it comes to tools there are some that will never have enough, then there are those that want to help you spend your money, they will also tell you where the money should be spent, please do not include me in that category.

It is not possible to start over by full length sizing a case that has been fired 'X' number of times. 'keeping up with more than one thought at a time' there is spring back, work hardening, brass migration (stretch and or flow), in the perfect world the case is new, unfired, annealed and forgiving, neck sizers create their own problems, from the beginning cases have filled the chamber when fired, neck sizers fill the chamber before firing, 'keeping up with more than one thought at a time' again. I limit head space by controlling shoulder set back and limit case expansion in the chamber with the versatile die, the full length sizer die and the use of the companion tool to the press, the feeler gage.

I can full length size a case, that is what I would do if I did not have a clue, I determine head space first then transfer the measurement to the press when I adjust the die to the shell holder, there are times when the difference between full length sizing a case and a case that fits my chamber is .016 thousands. So I do not mindlessly size a case by following instructions, and if the lights went out when the bolt closed, I would smoke the case, on one rifle the gap between the top of the shell holder and bottom of the die is from .009 to .010 thousands, that means when I fired the cases in that chamber, I applied the leaver policy, on fired cases, I leaver the way I fired-er.

There are those that do know the effect full length sizing has on a case and no way to determining the effect the sized case has on head space, so they go straight to neck sizing, for me on some chambers that is a jump that eliminates as many as 10 options and that is not taking into consideration full length sizing creates AT LEAST .005 head space when instructions are followed, yes neck sizing is an option, for me I have never used up all the other options available before I ran out and was forced to neck size.

Desperate neck sizing and wildcatting, that is different, there are full length sizer dies that can be used to neck size like the 7MM Remington sizer die when neck sizing 7mm wildcats.

F. GUffey