6.5X55 case necks breaking off

[bearbud]

This is something that didn’t happen to me until now and I wonder what the cause is. I had many split necks in the past but always in parallel with the neck and never like this. This happened to a batch of 20 cases and all of them show it to a different degree and length as shown in the pic. These are 6.5X55 PMC cases with about three firing before this one. The cases were not in use for about fifteen years but annealed just before this last reloads. Two loads (10 and 10) both were using mid-range book loads of RL-15 and jacketed bullets. (Hornady 100sp @ 2860fps and Sierra 140BTSP @ 2450fps) The rifle is Husqvarna M38 that never showed this in the past.
The way I annealed this brass is no different than what I always do and that works well for me. (Propane torch for 4-5 second, air cooled etc.) I am aware of PMC brass quality and it is pretty obvious to me that something is wrong with the brass, but what is it, and why is this split direction?
284902

[Gtek]

Sounds like you have a pattern that has worked for a while and now the anomaly with THIS brass. With just information given I would suspect brass composition and remove any and all of that lot and move on and see what happens. The upside is it's not popping primers and eating your bolt face, the downside how well will the Swede vent if rupture occurs a little farther back? That one in the middle is spooky and would throw him and all his friends in the can!

[Whole Bunches]

Lube inside of the neck before resizing. That cured it when I was having necks broken like the middle one shown. Mine happened with new PPU 6.5x55 brass.

[1006]

Seems like I read, brass gets brittle with age.

[jim147]

Could be age. Might check the neck area of the chamber and make sure it is not rough and pulling them off on extraction.

[leebuilder]

I have loaded and reloaded many, many 6.5 and have never seen that happen ever. I do experience cracking length wise on the neck and the odd time into the shoulder. I would check every thing, dies, brass and rifle.
Be well

[243winxb]

Bad brass from factory. Or over working the brass, + Poor annealing job. Or a chemical came in contact with the brass. Ammonia is in many cleaning solvents.

In 223, i found outside neck turning gets rid of the donut that can be present in new factory brass.

https://www.thehighroad.org/index.php?media/federal-223-brass-from-1997.1278/full

Brass fired when new. Reloaded and stored since 1997. Nothing new, happened before with brass washed in a vinegar solution. But this brass was not washed, just wiped and loaded.The cause seems to be over working of the case neck when FL sizing. Loaded in 1997 IMR4198-20.5grs Win 55 gr fmjbt .

[243winxb]

This LC brass had the donut. The expander was almost impossible to pull thru the lubed case neck, when FL sizing in standard RCBS die. A Redding Type S bushing die will stop over working the brass. Or neck turning for standard dies works.
https://www.thehighroad.org/index.php?media/223-brass-avoid-vinegar-and-ammonia-products.480/full

[bearbud]

Thank you all for the replies. I value your input and it is much appreciated. At least I know now that this had been observed by other fellow reloaders. I can’t recall if I lubed the necks when I resized this batch, but if I did, I used Imperial dry neck lube that I use exclusively. I will make sure to do in in the future when loading “older” brass. I plan to shoot this rifle with factory loaded ammo to make sure that at least the rifle is ok and to just toss this brass batch in the recycling bin and move on.

[Gtek]

I have become very fond of the Hornady spray can for normal duty, heavy work the Imperial tin still comes out.

[15meter]

Any chance being older brass that this was shot with corrosive primers?

Only time I had brass that I couldn't anneal was with VERY old 30-40 brass, I suspect it had been fired with mercuric primers. I annealed, same procedure as I have in the past with several thousand cases with no problems.

The 30-40 looked like any other annealed brass, nice color change, looked exactly like well annealed cases.

But they shattered like glass when trying to resize. The necks fractured or pulled off as if the brass was EXTREMELY brittle.

I suspect it is an ridiculously low chance, but if this is OLD brass that has been been around for a while it may have had a corrosive primer that ruined the brass.