Ingram Model 5
Gordon Ingram returned to the US after WWII with the belief that the simplest firearms were the most reliable. In 1946, he designed his own submachine gun, which he dubbed the “Model 5” (not because it was his fifth design, but to avoid confusion with the US Army’s M1, M2, M3 and to allow for an M4). Ingram struck a deal with the Lightning Arms Co., who managed to interest the Nicaraguan government with the design, but this amounted to nothing. In the end, only a single prototype was ever made. Here, in the only known photograph of the Model 5, a young woman (who I believe is Hope Portocarrero) demonstrates the simplicity of the Model 5.