partially split Lapua 6BR case neck

[Tokimini]

I found a Lapua 6BR case with an oddly split neck. The split starts about 1/3 of the way down and goes to the base of the neck. I've had split 204 Ruger cases before but they always started right at the mouth, never part way down. It's the only one I've found like this. The cases have been reloaded about six times and I anneal the brass every other firing. I do not load hot. I'm using 107 gr Sierra MKs with 28.5 gr of Varget, which is below Hodgdon's max. The barrel is a McGowen 8 twist and has about 600 rounds through it. Is the case defective?

 

[JeffG]

I've had this happen with 219 Zipper brass, neck sized from 30-30 and 25-35. I always assumed it was from over working the brass during neck sizing.

I'd guess the culprit was annealing, but someone else who does it every reload should contribute their experience.

In any case, brass is cheaper than shrapnel in the face so it might be time to retire that whole lot of brass.

 

[Tokimini]

Annealing softens work hardened brass and helps prevents splits, so I doubt annealing is the culprit. Since I started annealing 204 brass 2 years ago I have not had a single split neck and some of those cases are pushing 20 realoads.

 

[LRPV]

It looks pretty similar to a Dasher case that splits while fireforming to me. Some cases you can tell are going to do it out of the box, some you can't. I've split them hydro forming and fireforming. My guess is that as a BR it was just able to hold up for awhile before letting go.

 

[Old Navy]

It looks pretty similar to a Dasher case that splits while fireforming to me. Some cases you can tell are going to do it out of the box, some you can't. I've split them hydro forming and fireforming. My guess is that as a BR it was just able to hold up for awhile before letting go.

+1 Later! Frank

 

[ridgeway]

Yep, this defect is the direct cause of a Dasher fire form failure. Nothing new....been like this for years. Can it and move on...

 

[cocopuff]

I have had the same with lapua brass,after maybe 10 to 12 fireings..It is the nature of brass...But I also have some that have been fired 20 times and no splits...???

 

[lpreddick]

just curious...what is the chamber's neck diameter? what is the loaded neck diameter? what is the sized neck diameter?

 

[r bose]

I've had 223 brass split just like this and oddly enough, sometimes in 2 or 3 places on the neck at the same time.

 

[GrocMax]

During forming the straight walled brass slug is folded over evenly many times to reduce the diameter in the shoulder and neck, occasionally, there is a double or skip in the fold, which leads to this. All brands suffer from it, and you can see the fold lines in the brass and some will have a small line or gap, these are the ones that end up splitting like that.

 

[fm1947]

I have had 3 necks do the same thing lately but they have 20 reloads on them , same 6 br, lapua brass, funny thing I never annealed until maybe 4 loads ago then I got the splits, but I'm sure they just been loaded to much.

 

[CaptainMal]

Looks like a normal, common failure. No big deal.

Unless the neck area of the chamber is kind of big and the neck die is kind of small so the expansion/squeeze is greater than normal, that should not happen often.

 

[cocopuff]

So whats new? I had 2 brand new Lapua 223 cases split the necks on the first fireing....I am thinking to switching to Norma brass..It last so much longer I hear..But not everything is like some say it is.But I do know I had 2 split at a match...Caused me 2 points and you well know..