Not sure of the exact age, but I've fired a lot of military surplus and all of was at least 40 years old. No problems at all.


The surplus that I've heard that can give problems is Iranian 30-06 (back when the Shah of Iran was our ally and we were giving them guns), and then that Paki ammo someone mentioned.


Yugo 8x57 can be a problem because of hard primers. A weak firing spring won't always detonate it. I've got Yugo sniper ammo in that caliber, but that doesn't have the problems.