When U.S. Repeating Arms Company took over production of Model 21, Pigeon Grade was dropped from the line. Grand American Grade was retained with all the features of its predecessor, with the addition of a small-bore set featuring 28-gauge and .410 bore set of barrels. Two new grades were introduced in 1983: Standard Custom Grade and Special Custom Built. In addition to these grades, the factory would undertake to build for its customers whatever was desired. Due to the unique nature of these guns, it is advised that an expert appraisal be sought to establish a value. While the changeover from Winchester to U.S. Repeating Arms was a transfer of business assets, craftsmen and personnel remained the same. Collectors are reluctant to assign the same values to U.S. Repeating Arms Model 21s as those produced by Winchester. No official production figures are available for U.S.R.A. Model 21s, but the number is most likely small, perhaps around 200 guns.