Beginner needs help - 30BR

T

tiny68

Member
Let me start by saying I have never turned necks. So, I may be making some huge errors. Feel free to point this out. Trying to make some 30BR cases for new project rifle. Chamber is a 0.332 neck. I planned to neck up 6mmBR cases using the Redding tapped expander on my FL Redding S type die with the neck bushing removed. That seems to work fine. Then I was trying to use my K&M neck turning tool to turn the necks do to 0.011". I used the K&M expander to get the cases to fit the mandrel. Problem is that the necks are already only about 0.0100-0.0105 thick. If I turn them just enough to clean them well, I am at 0.0092-0.0095". What am I doing wrong? These parent cases are once fired 6mmBR Norma. I don't think they were pre-turned as 6BR cases. They were freebies. Maybe so. Do Norma brass have thinner necks than Lapua brass?

Thanks for tips. I have many questions to follow. tiny
 
tiny68 said:
Let me start by saying I have never turned necks. So, I may be making some huge errors. Feel free to point this out. Trying to make some 30BR cases for new project rifle. Chamber is a 0.332 neck. I planned to neck up 6mmBR cases using the Redding tapped expander on my FL Redding S type die with the neck bushing removed. That seems to work fine. Then I was trying to use my K&M neck turning tool to turn the necks do to 0.011". I used the K&M expander to get the cases to fit the mandrel. Problem is that the necks are already only about 0.0100-0.0105 thick. If I turn them just enough to clean them well, I am at 0.0092-0.0095". What am I doing wrong? These parent cases are once fired 6mmBR Norma. I don't think they were pre-turned as 6BR cases. They were freebies. Maybe so. Do Norma brass have thinner necks than Lapua brass?

Thanks for tips. I have many questions to follow. tiny
Click to expand...

Tiny, my Lapua brass out of the box is .0125, by necking up so far, that is probably the culprit. You may have turned brass as well. I do not know how much stretch you will get from the Lapua but if I were starting a project like you I would have new brass and make it the way you want it. Good luck with your 30br. Ron Tilley
 
Neck turning for 30BR

The best way I have found is to turn the necks, load a bullet and measure the overall "Loaded Neck" dimension. This should be approximately .002" under your .332 for fired round clearance.

I have the K&M & really like it.

I normally expand the necks, full-length resize, run over the .308 mandrel/"Expandiron", then turn the neck with a carbide "donut" cutter mandrel on the K&M. Then load a bullet & check the "Loaded neck" dimension as above.

Hope some of this helps.

Bill
 
More info

I guess I should have stated this in the beginning. The rifle came with about 75 new pre-turned Lapua brass. They all were turned to 0.011". The loaded rounds with this brass run 0.329-0.330" That seems to be my target, 0.011". I was just playing with this Norma brass to learn how to use the K&M tool.

Still a little fuzzy about setting the bottom screw so that the case only goes up to the doughnut? Doesn't seem to work on the length of screws that came with my expander.

tiny
 
I don't think you are doing anything wrong the necks on the brass you are turning may not be as thick as the Lapua after being necked up. You can't remove mat'l that is not there to start. I have used Rem 7BR cases and came out with a neck thickness of about .0085 and was just removing enough mat'l to clean up the neck. The screw on the expander is longer than it needs to be so I don't use it just be very careful when necking up cases.
 
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