Looks like an earlier M21- as from the pg shape and checkering pattern. Extractors or ejectors? Like the Fox guns, the m21 in 16 and 20 gauge had the same size frame- nice lines- $4K range, depending on ejectors or extractors. IMO- and I only own 1 Model 21- a 1949 era field grade 12- 28" SST, Ej- SPFE--I am no expert, and also my SWAG reflects my basic avoidance to the 16 gauge offerings- mainly due to higher shell cost than with a 12. I would not own this M21, which I like for pheasant hunting, except for the kindness of a bachelor uncle, who willed it to me.
