.338lm A few neck cracks - is this normal?

[jmptx]

I have been reloading .338 LM for about a year now. I have several batches of 50 rounds (Lapua Brass) that I have been working though. Tonight I was re-sizing my "batch 1" and found a few with neck cracks. Batch 1 has the following reloading stats on it: 1 Full length and 3 Neck Sizes (4 if you counted today). In other words I have shot them 4 times.

I have been running the same 92gr H1000 Chronographed @ 2771fps (magneto speed) and not had any issues.

I culled 3 pieces of brass with cracked necks out of the 50. I have not seen anything wrong with the other batches yet, but they have less firings by one or more.

For the record, I have just started annealing my brass with a Bench Source, so I am hoping to protect the necks a bit more. My other batches have between 1 and 2 less firings, so they might last even longer with the addition of the annealing step. I plan on annealing after every firing.


My question:

Is this normal for 338lm to start having failures this soon? Is there anything I might be doing wrong, or might do better?

 

[ChrisGarrett]

I had a Norma 338LM split after 2 cycles. The other 19 are still going fine after 8-9 cycles and a couple of annealings. Out of 80 new Lapua and anywhere from 11-13 cycles on the batch, I've never have had a neck split. I did get one stuck in a 'normal' kinetic bullet puller and had to wrench it out, but that was my fault.

2 after four cycles? That's a lot.

Chris

 

[jmptx]

Yeah, it seems like a lot to me as well.

However, I have no reason to think (yet) that I am doing something wrong. So far none of the other 150 pinches of brass have issues. I am just concerned that maybe I am doing something wrong.

Any other ideas out there folks? Am I just over-analyzing a few pieces of brass and I need more data?

 

[BuzzBoss915]

A pic might help? What exactly do you mean by: "neck cracks"? Split necks? I don't shoot that caliber but whatever the cause, seems excessive. BB

 

[oneshot.onehit]

I have 2300 rounds through the 338LM and run hard, I had a few necks starting to crack around the 4th or 5th reload so I started annealing and that was the end of that problem, a bunch of my brass is hitting the 12th round.

Lapua brass
300 grain Scenars
H1000

Cheers
oneshot.onehit