Brass question, fire form vs Full length resize in bolt gun.

[RussellC]

Was just over on rifle forum, where I queried about variances in fire formed brass with new Winchester Brass in Savage 12 FV in .223 Remington.

After being assured this is no big deal, (variance of 1.4540 to 1.4600) i being only .002 difference,

I have a reloading question. I know once upon a time the common practice was to neck size only for a bolt gun.....

Seems many are now suggesting to go ahead and Full length resize, setting shoulder back .001 or so. Measuring before and after, this is about all it moved anyway.

OR, should I neck size only for one more firing, then full length resize? Dies are Redding Competition body die, Competition Neck sizer with appropriate bushing, and Redding Competition bullet seater.

Or.is this an exercise in futility and I should just resize and reload as usual?

End reasoning here is tighter groups, accuracy, precision etc. obviously not efficiency or time saving.

Thanks in advance,

Russellc

 

[243winxb]

Neck size only, till you have a crush fit when closing the bolt. Now measure head to datum. Write it down. Bump shoulder back from there.

It takes 3 or more firing for brass to fully expand to the chamber.

Then test neck sized vs fl shoulder bumped.

You may find best accuracy sizing only 1/2 of the neck with the bushing , when fl sizing.

 

[RussellC]

Neck size only, till you have a crush fit when closing the bolt. Now measure head to datum. Write it down. Bump shoulder back from there.

It takes 3 or more firing for brass to fully expand to the chamber.

Then test neck sized vs fl shoulder bumped.

You may find best accuracy sizing only 1/2 of the neck with the bushing , when fl sizing.

Thanks, this is just the info I have been looking for. Case length is still well with in spec, so no trim necessary. I will neck size only and do it again and follow your advice regarding only 1/2 of the neck, I have been a little more than that, didn't seem to be able to get much more without making die tighter than Redding recommends. Seems to make sense.

Russellc

 

[243winxb]

regarding only 1/2 of the neck, I have been a little more than that, didn't seem to be able to get much more without making die tighter than Redding recommends

My Redding type S fl sizing die's bushing is adjustable without moving the die. Different then yours.

 

[RussellC]

My Redding type S fl sizing die's bushing is adjustable without moving the die. Different then yours.

I have that one also.....Full length sizer, uses neck bushing but no micrometer, right?

Russellc

 

[243winxb]

Yes,

 

[RussellC]

Yes, View attachment 796594

That's it. I've never used this one.

 

[243winxb]

The shoulder may move forward faster by fl sizing (body die) with a gap of .005" between the shell holder and bottom of the die. See if sized brass will fit the chamber.

 

[Varminterror]

If you don’t yet know your true chamber headspace, don’t bump the shoulder. Thrice fired and neck sized brass should close with a crush fit, if it closes at all. Once you know the true dimension, FL size to bump from there.

For precision loading, I prefer to body size with a Redding S bushing die, without the bushing, then neck size with a neck bushing die, then expand with a Sinclair mandrel.

 

[Toprudder]

If you don’t yet know your true chamber headspace, don’t bump the shoulder. Thrice fired and neck sized brass should close with a crush fit, if it closes at all. Once you know the true dimension, FL size to bump from there.

For precision loading, I prefer to body size with a Redding S bushing die, without the bushing, then neck size with a neck bushing die, then expand with a Sinclair mandrel.

Interesting. Is there a reason you do the body and neck separately? It would seem to me that doing the body and neck at the same time would better insure concentricity between the body and neck.

 

[Varminterror]

Contrarily. I size the body to be concentric to where it wants to be in the shellholder and die, then the neck bushing is set up to float, so the body guides the neck to center.

It also gives me the option of neck sizing only without any adjustment to my dies, if I get a wild hair and decide not to bump the shoulder.