I've got 30-06 ammo, about 500 rounds left, that are from WWII!!!!!! They are corrosive, but I don't care when I shoot them out of an old beat up M1 Garand. Immediately after shooting, I clean the barrel/action in the field. Never had a problem.

I agree with everyone here. As long as the bullets are kept in a dry, normal temperature area, they will last for a long time. Mine are going on about 46 years now. I bought them about 2 years ago form someone who kept them sealed in air tight ammo cans. They work like a champ and kill coyotes with ease.