Home Forums Hunting & Shooting Ask The Gunwriters Neck splitting on 30-06 brass

I discovered tonight that 11 of 15 brass necks were slightly split lengthwise after my last range visit. They were fired in a Remington 700 LSS with 22" barrel. The brass was once-fired. The 15 were loaded with 5 of each of the following:

59 gr IMR 4350 - avg = 2677 fps
59 gr H4350 (lot A) avg = 2689
59 gr H4350 (lot B) avg =2752

165 gr Sierra Gamekings
Winchester brass (once fired)
WLR primers
COL = 3.350"

Note the velocities are on the low side for this load. What do you think? Bad brass or very sloppy chamber? The latter would explain the low velocities.

I looked at the brass from a few Hornady and Remington factory rounds fired the same day. Those looked fine.

Is it a factory chamber? Are you noticing any blackening of the case necks? Just because the velocities are low for the caliber doesn't guarantee your chamber pressures are not too high.

It is a factory chamber.

Anneal them

Bad brass. Toss the whole lot if you only have a few.

I want to make a cast of the chamber to check dimensions. Brownells sells cerrosafe for this purpose, but I've heard of sulfur, which is much cheaper, being used. Any tips?

Use Cerrosafe, not sulfur is my tip..Its easier to use IMO..

Sounds like bad brass, but your smart to take a chamber casting, in fact, everyone should do that with all their rifles IMO, so they know the deminsions of their chambers.

I saw a handfull of Winchester .30-30 brass that was split, some necks and some shoulders last time I was at the range. I believe it was the first firing.

I had some bad 30/06 cases this summer that were splitting or crumbling when preping them for their first reload. I think they were from some old Remington factory loads someone had given me. They were pitched.

The velocities might be low, but those loads are HOT!

The brass is most likely the culprit. Old ammunition typically splits necks on the first or second firing. What is the history of these cases?

My recent Remington 300 Winnie is real hard on case necks. Even if I anneal, I'm lucky to get 4-5 reloads from it.

With brass of unknown provenance, who knows. If the problem repeats itself with different batches of NEW brass, you most likely have a sloppy chamber up in the neck area, causing the brass to get overworked real fast.

Or so the 'spurts told me when I asked a similar question.