Brass trimming question .338 Lapua Mag.?!?!?!?

[Darkphage]

Ok so specs for new .338 lapua brass length is 2.724

The chamber length on my TRG42 (carefully measured 8 times and averaged)

is 2.760.

My question is -- what should I pick to be my trim if longer than this length?

What is the best rule of thumb regarding brass trimming length for a rifle with a measured and known chamber length?

2.740? Or is that too long?

Both guides mention not zipping the brass back to factory specs -- but neither give a solid idea of exactly what is considered safe.

Thoughts appreciated.

Thanks
Dark

 

[ChrisGarrett]

Re: Brass trimming question .338 Lapua Mag.?!?!?!?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Darkphage</div><div class="ubbcode-body">Ok so specs for new .338 lapua brass length is 2.724

The chamber length on my TRG42 (carefully measured 8 times and averaged)

is 2.760.

My question is -- what should I pick to be my trim if longer than this length?

What is the best rule of thumb regarding brass trimming length for a rifle with a measured and known chamber length?

2.740? Or is that too long?

Both guides mention not zipping the brass back to factory specs -- but neither give a solid idea of exactly what is considered safe.

Thoughts appreciated.

Thanks
Dark </div></div>

2.724" is the max IIRC and 2.714" is generally the trim to length.

Most people measuring the chamber will trim .010" under what they find, to be safe. You don't want to start pinching the bullets and increasing pressure.

Chris

 

[427Cobra]

Re: Brass trimming question .338 Lapua Mag.?!?!?!?

I do .010 less than chamber measurement, but on a magnum I think I would do .015-.020