Not MILSURP

[painter777]

But it seems the 16 gauge is history nowadays?

16 shotguns are still being made. For shells, Ammoseek lists #2 - #8 shot and some are making different style /weight slugs.
In my collection I have and sometimes use my Grandfathers Browning sweet 16 to turkey hunt. When I order shells I order extra for my neighbors 2 daughters who shoot clays with 16's in a youth club. Rare for our small local shops to carry a decent selection if any at all. For a shotgun I grew up shooting a 28 gauge