New primed brass failing.

[Dave C.]

About 15 years ago I bought 500 new (41 mag) primed Winchester brass. I loaded them all the same. The load was from a Spear book of the time.

400 of this batch of brass have been loaded 23 times with the same load and are starting to fail a few cases each time, so I am going to recycle them. Now here is the odd part. I found the other 100 rounds that have been loaded for 15 years but not fired. When I shot these loads 15% of the cases split from the mouth to the web of the case! They are all stored under the same conditions (in plastic ammo boxes, midway 100's and in 50 cal steel ammo cans). They were stored 5 foot apart in a room that is temp controlled. So what happened?

Dave C.

[nhrifle]

Its probably the same thing you will run into with aluminum, age hardening. I once got some old brass from a friend that hadn't been touched in many decades. I loaded them moderately and wound up with a similar failure rate. Most of mine were just cracking the necks tho.

[zuke]

I believe it come's from left loaded and the constant stress of the bollet held by the brass.
There's a lot of pressure there over a period of time.

[williamwaco]

We had this discussion a few days ago.
Many say it does not age harden.
I believe it does.

I have seen unfired military surplus ammo unfired with split necks.

.

[high standard 40]

I have had issues with brass cases failing just as you have noted. Some failed on the first reload (44 mag), and some that were new cases and left loaded for a number of years and would split in the neck without firing (223). I am not referring to brass that fails from multiple firings, everyone will encounter that. I have also seen Winchester factory loaded shotshells, new and unfired, split the brass case head. Oddly, I have only had this issue with Winchester brass.

[nhrifle]

I'm still going with age hardening. A few years ago I got a box of very old 45/70 line throwing blank rounds from a friend. I didn't want to shoot them because they were historical, but I had to shoot a few. Every single case I fired had huge splits in it. And these were blanks! Almost no pressure whatsoever.