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Making 7mm-08 from 308 Lapua brass

BradleyH

Private
Full Member
Minuteman
Mar 15, 2013
109
7
Casey, Illinois
I have a decent amount of 308 Lapua brass sitting around (unfired) and would like to load up some 7mm 140 Bergers for my 7-08.

Is the process pretty straightforward or are there flags I should look out for that could possibly make it unsafe?

I will be using full length 7mm-08 dies.

Thanks
 
When you neck your 308 brass down, the neck diameter of you chamber and the neck wall thickness of your brass, can make the difference between a simple step down or needing to also neck turn the brass.

So also consider the chamber design of the rifle, and the desired thickness of your finished brass.
 
I've necked it straight down with no issues at all, but as pointed out above, you'll want to check your neck thickness.

I'd be more concerned if was was going to 260 or 243.
 
I have found that I need to ream the necks.
 
I have a decent amount of 308 Lapua brass sitting around (unfired) and would like to load up some 7mm 140 Bergers for my 7-08.

Is the process pretty straightforward or are there flags I should look out for that could possibly make it unsafe?

I will be using full length 7mm-08 dies.

Thanks
One of the things I did was NOT lube the necks (expander ball). That helped stretch the necks just a little. Taking you from 2.015" to 2.025". Which is like normally trimming back a case.
With the extended distance of the case neck to the throat, you do cause a bit more wear in the throat.
Eventually, I terminated all my .308/7-08 brass in favor of straight up 7-08 Lapua. The .308 necked-down brass, did really well (11-12 loads). I just had to watch it more closely.