When the Model 21 Skeet Gun was introduced, 1932/33 it was offered in Tournament, Trap and Custom Built grades. By 1936, Winchester dropped the Tournament Grade, so beginning in 1936, the Model 21 Skeet Gun was offered in Standard, Trap and Custom Built grades. During 1939 the Trap Grade was dropped and replaced with the Model 21 Trap Gun (12-gauge only) leaving the Model 21 Skeet Gun in Standard Grade or Custom Built Grade for 1940 & 41. By 1946 the Custom Built Grade was renamed the DeLuxe Grade. Up through 1946 the catalog barrel length for the Model 21 Skeet Gun was 26-inch by the 1948 Winchester catalog the barrel length was upped to 28-inch. By the January 2, 1952, Winchester Catalog the DeLuxe was gone and the Custom Built Grade was back. Throughout its production run the Model 21 Skeet Gun it was offered with either a straight grip or a pistol grip. Pre-war rhe pistol grip was offered either with or without a cap. The butt was always checkered. A big drop in "collector" value if the bare wood checkered butt has been replaced with a recoil pad. The Skeet Gun always was standard with ejectors, single-selective trigger and beavertail forearm. The extra cost option of a ventilated rib first appears in the 1938 Winchester Catalog, after the Tournament Grade was gone.