This is an extremely rare example of an early prototype Taft-Peirce manufactured Johnson receiver, from circa 1939, assembled into a functional semi-automatic rifle using subsequent standard production Johnson Model 1941 semi-automatic rifle components. Born to a very affluent Massachusetts family, Melvin Maynard Johnson was commissioned into the Marine Corps Reserve in 1933 and completed Harvard Law School in 1934. He was always fascinated with firearms and mechanical devices, so he was posted as an observer at Springfield Armory. During this time, he witnessed several poorly designed rifles brought forth for military testing, and even expressed concerns in things he believed to be shortcomings in the early prototypes that became the U.S. Army adopted M1 Garand; most notably the early gas trap system being prone to carbon build up. Johnson commenced work on his own design in 1935 and searched for contractors to manufacture his prototypes. His rifles employed a recoil-operated system with a rotating bolt. This Taft-Peirce manufactured receiver, wearing serial number "R-13", is one of only 7 rotary magazine Johnson prototype rifles made for military testing with a ten-round internal rotary magazine, referred to as the "Type R" in reference to its rotary magazine, and similar to the final form seen in what became the standard production Johnson Model 1941 semi-automatic military rifle. This specific rifle was used extensively for military testing and was one of the three rifles used during the U.S. Marine Corps trials at Quantico in May of 1940 to determine if the U.S.M.C. would field a semi-automatic rifle in place of the 1903 Springfield bolt action rifle. Serial number "R-14" Taft-Peirce rifle, one number after this gun, currently resides in the Cody Firearms Museum collection wearing Winchester factory collection tag "W 49" and has a full length wooden handguard. Minute differences can be seen in the overall shape and design of this prototype receiver when compared with a production Johnson Model 1941 semi-automatic rifle. Although the production Johnson Model 1941 rifles were ultimately unsuccessful in gaining U.S. Army interest, most of the 21,400 manufactured were sold to the Netherlands Purchasing commission, and the U.S.M.C. acquired approximately 750 Model 1941 rifles and used them in the early Pacific island hopping campaigns. These rifles employed several unique features such as the rotary magazine which allows reloading at any time, and a recoiling barrel that has the ability to be easily removed from the rifle by hand for takedown, which allows the rifle to be stowed in a parachute jump bag. The rear, right side of the receiver is marked "TAFT-PEIRCE/WOONSOCKET, RI USA", and the top of the receiver is marked "JOHNSON AUTOMATICS/SEMI-AUTO .30-06/U.S.A. PAT. 2094156/2146743/PAT. 1938 CANADA/R-13" in six lines. Blade front and 1,000 meter rear sight base. The Model 1941 barrel locking bushing has the markings of "41" for the year and "30-06" on the front flat. The Model 1941 barrel is numbered "5105E" on the lug. The Model 1941 bolt is numbered "B9009". Model 1941 rotary magazine assembly. Fitted with a two-piece walnut stock and forend. Absent front sling swivel. This is one of the few surviving examples left today of a Taft-Peirce manufactured Johnson prototype, and serves as an important evolutionary piece in the story of what became the Johnson Model 1941 semi-automatic rifle.