Not a vintage double, but this is the first Remington Sportsman C-Grade I've seen. Up for sale on one of the boards.
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From its introduction in 1930 (20-gauge) and 1931 (12- and 16-gauge) The Sportsman was catalogued in the C "Trap" Grade through 1937. No The Sportsman C "Trap" Grade in the catalogs from 1938 onward.
So far I've recorded three The Sportsman B "Special" Grades, all in 12-gauge --
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I've yet to see a Remington Model 17 or 31 pump marked as a B-Grade. Every one I've seen advertised for sale or pictured as a B-Grade IMO is just an A "Standard" Grade from the time period that they came with checkered wood, 1929 to 1937.