5.56 mil split necks?

[Typecaster]

OK, I'm having a long-distance "discussion" with my dad, a 96-year-old former gunsmith, about the wisdom of using milsurp 5.56 brass. The "discussion" part is tough because he lost his one hearing aid, not that it helped much anyway, but I want to give him a distraction from my mom, who is in a hospice care situation.

His contention is that my .223 brass is suspect because most of it is about 40 years old. He remembers a lot of split necks in the '50s when he used WWI-era 30-06 military brass--it was about 40 years old at that time. I think the problem was from having corrosive primers, a non-issue for the .223 stuff. I

I've been using it as .223 and reforming into .222 and .25/222 for years...never had a split neck. I know that's anecdotal, but that's my reality. He doesn't think I should bother separating my last big batch of cases--my M.O. is to separate by headstamp and year. OK, he has my last 6,000 cases in Arizona and has volunteered to separate them, but we're still having the discussion.

Any consensus from the board?

[BruceB]

Back in the "glory days" before GCA 1968, it was very common for importers to offer huge batches of military-surplus ammo, ALL with split necks, and advertised as such. Typically, the stuff was several decades old, often of war-time manufacture, and frequently from third-world factories. The ammo was sold for salvage prices.

Technology has come a long way since the early years of the 20th century, and I would certainly not worry about your military 5.56 cases splitting any time soon, or at least until you've loaded and fired them quite a few times.

When you get to sorting the stuff, make sure it doesn't include any BERDAN-PRIMED cases....yes, they do exist in 5.56; I found a couple just a few days ago when sorting-out another batch of range-pickup 5.56 brass.

I don't believe that the primers will be affecting your brass, as mercuric priming is very much a thing of the past. Mercury from the primers causes embrittlement of the brass after firing. I'd be very surprised to find 5.56 brass of ANY manufacture which used mercuric primers, and certainly, U.S.-made ammunition hasn't used such primers in at least fifty years, and then only in a few calibers of match ammunition (early '50s in .300 H&H is the last use of which I'm aware).

Enjoy all that brass.

[HORNET]

FWIW, the .223 brass that I'm still using is some 5.56 RA'66 brass that I've had a looong time. This is mostly used in bolt-guns and does require annealing after about 5 firings or so to reduce split case necks. I have absolutely no idea how many times they've been reused but its a bunch. They may not need as much annealing now that I have a Lee collet sizing die that doesn't work the brass as much.
Those Berdan-primed cases do tend to be rough on decapping pins if you don't catch them.