However, no problems during several cases of ammo, so odds are "It's not that old!"
I stood side by side in a duck blind and boat for years with a eccentric Finlander and noticed one day that he had some 3" shotshells in his ammo can. When i asked him about them he said he bought a couple boxes the last season and just tossed them all into the same can, un-boxxed. He was shooting a 1897 Winchester. He picked up several empty hulls that he ejected out of that gun and it was obvious that the chamber didn't fit the 3" empty.
As a youngster we used to have to close the old Ranger SxS .410 over the knee when we loaded it with 3" shells. All it says on the barrel is "Proof Tested 410 GA". And I swear that there were 2-1/2" Magnum shells back then that kicked harder than the 3".
If i remember correct they were purple.