35 Remington, cracks in neck, reloads

[nitro-express]

I've experience 2 case failures out of the 13 shells I fired.

The rifle is a Marlin 336A circa 1951, in 35 Remington, that I just bought from a friend, and it's in decent shape, no visible concerns. The ammunition came with the rifle, reloads, more than 20 years old. They are 200 gr RN bullets, loaded in FC brass. The cases are still bright, as is the jacket on the bullet, the lead nose is a bit grey. They are not high pressure loads, well below max, and fairly accurate.

I suspect the combination of thin brass, 0.010, in the neck area, age and a generous chamber were too much for the brass. The neck expands 0.005" over loaded diameter and the diameter just below the shoulder expands 0.008". Headspace, or shoulder setback, has been checked and it is not an issue. I trust the quality of the reloads, but what the reloading recipe was, is not apparent.

I'm not overly concerned, don't really need help solving this "BUT" I'd like to know if anyone else has experienced this with the 35 Remington? with any other calibers?

[nitro-express]

I fired off the remaining shells, no sense saving them. The picture is a little out of focus, same type of failure. If I resize the rest, I suspect a lot more will split. My dies should be here in a few days.

[Sheepcrazyguy]

I have a 1892 in 25-20. It happens with my older brass. I haven't tried anything to cure it. Just watch when I reload and toss the split ones. Off the top of my head I can't remember if I have my die set to full length resize or not. Also the ones splitting are old Remington loaded brass that I bought quite a few year ago. I don't shoot it as much as I used to but haven't seen this happen in the new brass I bought yet. I believe you're right in what you think is causing it.