I've shot old 16 gauge shells for years. As long as the shell looks good on the exterior, they kill doves fine. I bought a large lot of assorted 16s at an auction years ago, and have been using them ever since. I think I might have had one that sounded a little weak, but the rest have killed doves and crows just fine.
Gunpowder lasts a loooong time when kept cool and dry. Heat and moisture are it's enemies. I have a friend who found a War of Northern Aggression cannonball deep in the soil. It was fused but had never exploded, obviously. He opened it somehow, got some black powder out of it (it was really gray looking), loaded it in a percussion rifle and fired it. 120+ years old, at the time.
SRH
