VK35001 5,5cm Flak (VG) Gerät 58
The German ministry of War demanded for a mid size calibre anti aircraft gun closing the gap between the calibres 3.7 cm and 8.8 cm. Besides the 5cm Flak 41 which has been introduced in November 1941 Rheinmetall-Borsig as well as Krupp started with the development of an automated weapon with the calibre 5,5cm in 1942. Although Krupp could present a smarter design which was 300 kg lighter than the prototype of the competitor, their tesing results were not convincing. Consequently Rheinmetall improved their gun and finalized the weapon as version two (VG2 = Versuchsgeschütz 2) in 1943. The final version has been produced in February 1945 but there is no evidence that the gun ever saw action.