My father and most of his deer hunting friends carried Lefever, LC Smith, and Ithaca double barrel shotguns (usually 16 gauge)until the mid 1960s. My father used 1 buck 16 gauge then-modern shells in those shotguns.
I never knew he even had a 12 gauge shotgun until he passed away. He had no 12 gauge ammo at that time. In his notes he wrote that he bought this 12 gauge LC Smith used in 1945, and added a recoil pad in 1947. It seems he later settled on 16 gauge and stuck with it until the mid 1960s when he switched to a .308 rifle.
This LC Smith is no beauty queen but everything seems to function correctly. It could be a wall hanger but I hope for something better than that.