Old reloads - split cases

[COgunner]

I recently found a box of .44 Mags that I loaded about 30 years ago. The label on the box indicated "new brass" - Winchester brass with red paint still on the primer. Upon inspection, I found that 15 of the 50 rounds had hairline cracks running from the mouth about a third of the way down the round. I was really surprised to see this - I've used factory ammo older than this stuff with no problem.

I guess it's not likely that many folks are going to have reloads this old, but just wondering if anyone else seen this with older reloads? (Obviously, I'm not going to shoot any of the lot.)

[jepp2]

I have experienced split cases on handgun brass in the following calibers:

30 Carbine, 32 H&R mag, 41 Rem Mag, 44 Rem Mag

That is both for my reloads using new unfired brass and new factory ammo. Only with jacketed bullets, never with lead bullets which are 0.001" larger in diameter. Most were in the 20 to 30 years old range.

[Unclenick]

That sounds like typical season cracking. It's caused by exposure to ammonia vapor. You can read about it in the Wikipedia. Doesn't take much. Proximity to mouse droppings and urine will do it. Fertilizer breaking down will do it.

[COgunner]

Interesting - I've never heard of season cracking. Guess that could be it, but don't know how rounds could have been in presence of ammonia. These were jacketed bullets like jepp had problems with. Oh well, not too likely to happen again. Thanks for the input.

[BigJimP]

No, I've never seen that happen....I have some old reloads - handgun and rifle - and some old factory rifle ammo in my safe for calibers that I haven't shot in years.... .30-40 / old .30-06 200 gr bullets / some really old .38 spl and .357 mag...( where the lead bullets have oxidized a little at this point ) but no cracks in the cases... and some of them are from the 1960's...

I don't know ...

[F. Guffey]

Split necks? Could depend on how fast the neck expands as in BG!!! when compared to BAAAAANNNNNNG!

Then there is a reloaer with a press, dies and shell holders, it is beyond me how or why a reloader chambers a round, then pulls the trigger, and then finds there is a problem.

I form cases, I think nothing of forming 280 Remington cases to 338/06 or 35 Whelen. I think nothing of spinning cases to clean when reloading 20 cases for a new creation. I make spinners for cases that need to be cleaned, some are on the worst side of beyond cleaning in a tumbler. When spinning a case with a tapered tool crammed into the neck the neck has bullet hold or it splits.

Pistol cases, you have an expander? Use it, if the neck splits go to the next one, not a problem but if the cases are mixed and matched with different head stamps? I keep my cases separated when one splits I expect the next one to suffer the same fate.

Cases I form and do not anneal are expected to split because of the large chamber neck diameters.

F. Guffey

[Slamfire]

Could be due to powder deterioration.

The shooting community is ignorant of the fact that gunpowder has a shelf life and as powder deteriorates it causes more problems than it cures.

As gunpowder breaks down it releases NOx, this reacting with the water in humidity, one by product is NO2 acid gas, and this will crack brass and leave green corrosion spots inside the brass and on copper jackets.

Pull a couple of bullets and see if you have evidence of tiny green spots, like found on these US military bullets.



If so, pull the bullets and dump the powder. Old gunpowder can, has, and will blow up firearms, this is all due to burn rate instability. Some of the cases may be salvageable, but you will experience case splits on some or all of them.

[jepp2]

Just to add a bit more detail to the on the brass I had that cracked:

- I feel there was very little to no potential of exposure to season cracking. The loaded rounds were stored in closed MTM plastic case guards and there wasn't any urine, droppings, fertilizer, or any other source of ammonia nearby. I worked at a site that had extensive copper brine tracer that got bird droppings on it and had cracking issues, so I am fairly experienced at the symptoms.

- I pulled the bullets from the rounds I noted were cracked and there was absolutely no evidence of any powder deterioration. Smell still had the solvent odor, interior of the brass looked new and shiny still.

- I attributed the cracking due to very high neck tension. Since I was loading jacketed bullets, I used a very minimal flare to start the bullet. I didn't use the Lyman M expander on these. It is my understanding the military spec for 5.56 ammo specifically requires the anneal of the neck to avoid neck cracking for rounds that are stored for excessive timer periods.

Just my thoughts and added observations.

[dickttx]

A couple of years ago when I got back into reloading after about a 40 year layoff I checked all my previous loads and fired them. No problems with any except .357 Mag loaded in Winchester nickel cases, using Hornady 158gn jacketed hollow points. They looked OK but more than half of them split down the sides when fired. I didn't even notice it until the last cylinder full was fired. Went back and looked at all the cases and something like 16 of 25 were split. They were stored in CaseGard 50 round slip top boxes, as were all of them.

[Unclenick]

Jepp2,

Bottleneck rifle cases are all annealed from neck to shoulder to help prevent season cracking. Except for Lapua brand and military cases, the oxide is usually polished off, so you have to hold the case in the light just right to see a slight color change in the yellow that shows where it was done. But straight wall cases don't normally receive this treatment because, no bottleneck having been formed, they have less work hardening to start with. Seating tension alone isn't usually enough to cause the problem. I know some people have experimented with annealing the necks on handgun rounds, but if you look at where the mirroring of the base of the bullet in the case shows up, you soon realize you'd have to anneal down very close to the head to relieve the whole bullet gripping area, and annealing the head weakens the pressure seal and can lead to disastrous ruptures. It's never safe to anneal the head of any case in any degree.

Dies for handloaders often do resize far enough to cause more neck tension than the original factory loading did. That's because the factory knew exactly what thickness they were forming the necks to, where hand loaders resizing dies have to squeeze the brass down enough so the thinnest case with additional work hardening from repeated firing and resizing still gets small enough to work. But, that said, straight wall brass still usually survives a number of cycles of roll crimping before it starts splitting. A new case should not be that stressed, and should not have the issue at all.

So I'm thinking Dick is on to the most likely alternative to ammonia vapor exposure, and that is some fault in the nickel plating itself. Choosing the wrong plating chemistry or just using too hard or too thick a nickel plate (phosphorous content can normally be increased to make it softer) could cause it.