My elderly neighbor passed away back in the winter and his widow called me and said she was keeping all his guns to pass on but wanted to get rid of most of the ammo and asked me if I'd help her. He had a really nice stockpile of commercial hunting ammo, much of it dating back to the late 40's and 50's, so at least 60 years old.
She said she just wanted it gone if I'd haul it off, but I insisted she take $200.00 for it anyway. Lots of shotgun ammo, most of it paper hulled, including .410, 16 and 12 guage. A bunch of .30-06 hunting ammo, .30-30, .22 Hornet, and a case of USGI .30 carbine. Also a dozen bricks of .22 LR, a bunch of .38 Special, .45 ACP, and some .32 S&W.
I've shot some of each type ammo (except .22 Hornet, I don't have one of those) and all of it has worked flawlessly, including the paper hulled shotgun shells. No doubt this is due to his meticulous storage of his ammo stash all those years.