Im finishing up the remnants of some Malaysian stuff of the same era that I got back in the 90's for cheap. While I am shooting it up, the brass is showing signs of powder degradation, and the cases are failing when shot. 99% of those are split necks, with a couple of longitudinal splits in the bodies.
While I dont normally reload military brass anymore, as its generally a pain to prep, and the life is usually about 25% less than commercial. The past couple of years, I have been using it for blasting ammo, and just loading it to failure. A good bit of that, is some of the Malaysian stuff, and a good bit of LC dated from the late 60's. Both seem to have a much shorter brass life than the later stuff Ive been loading with it. Same failures in the brass as the loaded Malaysian stuff, so Im again thinking the ammo was degrading prior to being shot, and the brass was compromised.
One thing that got me to wondering about the Malaysian stuff, was that missing plane a couple of years back, and how they stored the batteries that were questioning. Those same conditions the batteries were supposedly stored in, arent good for ammo either. Something to think about. Ive shot a lot of surplus over the years, and some did have similar issues. Ran into it with old relaods a couple of years back too.
You may want to pull a couple of bullets, and look at the bases of them, and see if they have any bluish/green corrosion on them. Thats a sure sign, the powder is going. If so, probably best to shoot that stuff up, rather than put it back.