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Tight new lapua 308 necks. Options available?

jaycoux

Sergeant
Full Member
Minuteman
May 22, 2010
503
12
Central Texas
These suckers are tight. Can I use a K&M mandrel to expand them and then size them with my neck sizer to make them all uniform? If I do use the mandrel, how far down should I take it? Just part way or all the way down the neck?

Thanks for any advice
Jay
 
Re: Tight new lapua 308 necks. Options available?

I had that problem with some 7mmRM brass. I used the procedure you are suggesting; open them up with a mandrel, and then resize them to whatever you want. I did open up the entire neck.

Mine were so tight that a standard 7mm expander mandrel didn't work. The necks sprang right back! I had to get a 308 mandrel turned down to 0.288" or so to get my necks opened up.

Understand however that you are really working the brass, so your first annealing step might come sooner than normal.