A short time ago fredj338 shared his experiences with older loaded cases splitting in storage. (My thread was "Lube on Lead Saving My Brass", but Fred had posted his experiences elsewhere as well.)

In a nutshell, brass cases loaded with lead stored 10+ years were splitting IN STORAGE. Never having experienced this I looked through my larder and found my oldest lead rounds: 100 factory PPU LRNs, 5+ years in my ammo can (and who knows how long on the shelf before purchase), and 80 various handloads 4yr 0mo to 6 yr2mo old. (All my stored ammo is in .50 or .30 cal cans with big dessicant bags inside.)

Today I reloaded those 180 cases without a loss. I inspected each before firing over the past week or 10 days, then tumbled them in corncob afterward. I don't use liquids or chemical polishes.

I don't typically keep loaded ammo around for a decade or more. Those handloads were evolutionary dead ends, and all virgin or 1Fs brass. None of my favorite loads stored were over 3yrs5mo old. So maybe my sample was just too young.

Has anyone experienced this, or have thoughts/theories on the subject. Fredj338 has written on chemical welding, effects of humidity /moisture causing an electrolytic reaction on dissimilar metals, seasonal cracking (ammonia). I will toss out the idea of nitrocellulose decomposition (but that would not be perculiar to lead).

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The only stored ammo I've seen split cases on is 30/40 Kraig ammo from before WW I, and that very infrequently.

I've never seen it in handloaded ammo, or for that matter, in 22 ammo dating to the turn of the 20th century.

I have had that happen but only with Remington brass.I loaded a bunch of 357's about 30 years ago using Remington brass and Remington jacketed bullets.I spent the next 8 to 10 years in and out of the hospital and just forgot about the loads.When I found the loads some 12 years after they were loaded approximately 10 % of the cases were split.I have not seen this happen with other manufacturers brass.The cases were not nickle,they seem to fail even faster.

In the late 80's I had a 7X57 and loaded some Remington brass but did not fire it all before the rifle moved on. In 2013 I got another 7X57 and maybe 5% of the loads had split necks in storage. Quite a few more split on firing so I culled those brass from the herd.

Cases split at the neck usually indicate the results of metal fatigue associated with resizing. Such splits can occur at any time following repeated stresses during the reloading cycle(s).

Ammonia (or aliphatic amines) will embrittle brass by attacking zinc in the alloy. Ammonia is found in some cleaning solutions, and amines are a decomposition product of nitrocellulose, and also found in bore cleaners. EDTA, used for ultrasonic case cleaning, will also dissolve zinc. If you clean cases with a liquid, don't let them soak. Rinse and dry them thoroughly, ASAP after the cleaning cycle.

Military propellents contain diphenylamine as a smoke suppressant This can decompose in time. I smell amines when firing green-tip 5.56 rounds from the Vietnam era.

Tin will expand as it changes crystalline form with age. Excess tin should be avoided when mixing your own lead alloy. It also lowers the melting point of lead, causing leading even if the alloy is too hard to scratch with your fingernail.

I have a motley assortment of rounds I loaded nearly 50 years ago, which have survived without splitting.

Rpg, It did not occur to me but I have .22s over 20 years old, checked and ok. My father in law has some really old boxes "Central Hardware .49 c (no cents sign on this devise)"
Milton, I don't care for plated cases, just makes reloading more difficult. Of course for some it prevents thier ammo from welding to the cylinder or belt loops;-).
Twodog, my two companions like the tag.
Lobo, Yes, I wonder if the split cases were reloaded once or 23 times.
Neumann, I have read others on line reporting ammonia smells eminating from surplus (and pulldown) powders, decomp, supressant, doesn't really matter, ammonia and brass don't play well together.

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