Known as ".38/.44 Heavy Duty" before the change to numerical designations. This model was brought out in 1930, in response to requests from law enforcement personnel for a more powerful sidearm. This model, along with the .38-44 S&W Special cartridge, was an attempt to solve this problem. It was manufactured with a standard 5-in. long barrel but has been noted rarely as short as 3.5 in. and as long as 8.375 in. Built on the large N-frame. Blued or nickel-plated, with checkered walnut grips. Eventually the popularity of the .357 Magnum made the Model 20 superfluous and it was discontinued in 1966. Numbered model specimens are scarcer than pre-Model Heavy Duties. Total post-war production was about 20,000 revolvers. Two engineering changes.