The Lightning (Lightning / Flasher) was a submachine gun produced by the Home Army, or Home Army and the Polish resistance movement fighting the Germans in occupied Poland. A successful construction, it was probably the only bridge weapon designed and mass produced covertly in occupied Europe besides the Sten (British submachine gun)
In 1942 engineer Wacław Zawrotny proposed to the Armia Krajowa command that he and his colleagues prepare a project of a cheap, home-made machine pistol for use by the Polish resistance. Its main feature was its simplicity, so that the weapon could be made even in small workshops, by inexperienced engineers. The idea was accepted, and Zawrotny, together with his colleague Seweryn Wielanier, prepared a project of a sub-machine gun, soon afterward named Błyskawica (Polish for “lightning”). To allow for easier production, all parts of the weapon were joined together with screws and threads rather than bolts and welding, which were commonly used in firearm production ever since the 17th century.
The design was based on two of the most popular machine pistols of the era. The external construction with a retractable butt and magazine mounted below the gun was borrowed from the successful German MP-40. The internal design of the mechanism was modeled after the British Sten. Blow-back, with an open bolt, it offered good performance and high reliability. Unlike the British Sten (and its Polish clone called the Polski Sten) it employed a free-floating firing pin.
The documentation was ready by April 1943, and by September a prototype was ready. After extensive tests in the forests outside of Zielonka near Warsaw, the weapon was presented to the commanding officer of the KeDyw, August Emil Fieldorf, who found the design acceptable. In November the plans were sent to a number of workshops spread throughout occupied Poland and a serial production started. The name was coined after the three lightning bolts carved on the prototype by its designers, pre-war workers of the Elektrit company that used a similar logo.
Polish soldier firing a Błyskawica during the Warsaw Uprising
The production started in a workshop officially producing metal fence nets in Warsaw. After the tests of a prototype series of five pistols, the KeDyw ordered 1000, and later an additional 300. Until July 1944 and the start of the Operation Tempest roughly 600 pieces were built in Warsaw. During the Warsaw Uprising an additional 40 were built. It is also possible that the Błyskawica was also produced in small quantities outside of Warsaw.