Neck turn after annealing?

N

nonliberal

Guest
Im shooting a tight neck chamber and decided I would aneal a few pieces of brass to see if I could get a lower ES. I pulled 5 of the pieces that I was just shooting and annealead them. After I was done and the brass was dry I FL sized, loaded the rounds, and it would'nt chamber. I forced one just to see what was going on an it appears all the necks got thicker by annealing them.

I had the K&M turner still set from the last batch I did and it removed about .001. It chambered just fine after that.

Is this normal? Do you have to re-turn the brass after annealing on a tight neck chamber?

Thanks.
 
I have recently annealed all of my brass for my 6ppc and 30BR...I did not have and size change...
When I do the original neck turning I always turn down into the shoulder/neck junction about 1/16th inch...
I can't imagine how yours became thicker if it fit your rifle before annealing..
 
It had me confused as well. I pulled those five randomly from 50 pieces that I was shooting earlier in the day and continued to shoot them later. The five that I annealed were the only ones that the neck turner took off more material from the neck. The unanealed brass was able to turn with nothing more than a very little shining effect.

I will do a couple more and take measurements before and after.
 
It actually grows. I put my K&M in ice water so heat wasnt a factor. Then I expanded and turned the neck, put the K&M back in the ice water for a minute, resized and re-expanded the case and tried to turn the neck again. It didnt remove ANY material the second time around and it fit in the chamber. Then I annealed the case, resized and re-expanded it. It would not chamber. So I pull the turner back out of the ice water and it removed .0007 of material. Now it fits in the chamber again.

This was Lapua brass, I didnt notice a change with the WW brass when I tried it.
 
This is interesting :cool:

Is there any chance that you got some sort of "oxidation" or buildup of some sort from the annealing process? I'm just shooting in the dark here but did you quench them in water that maybe had an oxide present or something? If you spun them over a brass brush after annealing.........or polished them in and out with steel wool?? I read your post carefully, I can't see how its any sort of differential sizing issue.

I'm clueless here, just interested is all.


al
 
Thats a good possibility. I did quench them in water. I cleaned inside and out before annealing but didnt think about doing it afterwards because they still looked nice on the outside. If there was oxidation build up on the inside it could have made the brass expand more on the expandron mandrel. I will have to check into that.

Thanks
 
The different "spring back "of the case neck after annealing will affect the fit of the case neck to the neck turner mandrel. Measure the i.d of the case neck before and after annealing with pin gauges.

Turn a few cases by hand -without power . See if they are more consistent.



Glenn:D
 
I just did another one doing as Al said wire brushing the inside and out after the aneal as well and did the turning by hand like Stonewall said. It still grew a little but not enough to keep it from chambering.

Before anealing the wall thickness measured .0106.
After anealing the wall thickness measured .0108.

Doing it the other way it was going from .0106 to .01095 which was to much.
I guess the easy fix for this would be just not to have the brass turned so close to the chamber size.
 
If I had to guess, I'd say that the problem is your chamber is shorter than you think, or your brass has grown longer than you think, or you don't check that. Check the case length and trim the necks. Make a gauge from a case and one of the sinclair chamber length gizmos and find out what your chamber length is, then back off from there on the case length.

I'd say the only reason annealing had any effect is that for the first time, you actually were able to size a case, and so when the diameter shrank, the length grew.
 
4Mesh said:
If I had to guess, I'd say that the problem is your chamber is shorter than you think, or your brass has grown longer than you think, or you don't check that. Check the case length and trim the necks. Make a gauge from a case and one of the sinclair chamber length gizmos and find out what your chamber length is, then back off from there on the case length.

I'd say the only reason annealing had any effect is that for the first time, you actually were able to size a case, and so when the diameter shrank, the length grew.
Click to expand...

That was actually my first thought also so I put it in the Wilson trimmer that I keep set and it was perfect. All dimensions of the case are very close to the chamber, and the die was made from the same reamer as the chamber.

I first determined it was thickness because after the brass was ran up the expandron I carbon smoked it. Then chambered it without a bullet to see where the resistance was and it was consistant pressure on the neck diameter.

All is well now though because I just decided to deal with it and re-turn all the necks after anealing. It just seemed strange that I had never heard of that before.
 
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