This past weekend, I had a chance to fire an M1 Carbine I recently found in the bottom of a lake. My diving crew friends also recovered some ammo with the gun. Uncle Sam’s Lake City Army ammunition plant had loaded it almost 70 years ago. Stored in an ammo can in a detached garage for many of those years, the US government ammo ran flawlessly.
A couple of years ago I wrote here about how antique ammo stored even in less than ideal cool and dry conditions will still go bang reliably.