The gun's designer was Henryk Strąpoć (born 1922), a blacksmith and self-taught amateur gunsmith in the village of Czerwona Góra, Świętokrzyskie Voivodeship. Between 1936 and 1939 years he illegally built four semi-automatic pistols of his own design. During the German occupation of Poland he became a gunsmith for the local Bataliony Chłopskie underground organization. In spring of 1943 he completed a working prototype of his own submachine gun, later named Bechowiec. He later improved the design with a help of Jan Swat, who formerly worked as a mechanic in the metalworks in Ostrowiec Świętokrzyski.