The Turner .45 was designed by Russel J. Turner of Butler, Pennsylvania. It was originally a light rifle chambered for .30 cal and was submitted to the SRM-1 trials. It was rejected so Turner re-chambered it as a submachine gun for .45 ACP. It had select fire capability and used an Allen screw wrench adjustment system on the selector. The trigger mechanism consisted of a lock-and-pin system. The barrel was 15.2 inches long and had a perforated jacket surrounding it. It was tested at Aberdeen Proving Ground on both the 15th of September 1941 and the 16th of October 1942, both without success. Only one prototype was made.