 A. Lyamin and L. V. Lyuliev was successful, but the army thought that the 45 mm calibre was a little too large for an automatic field weapon.In January 1938 the Artillery Factory Number 8 in Sverdlovsk was ordered to develop a 37 mm weapon based on the same design.The task was fulfilled by the chief designer of the factory, Mikhail Loginov, and his assistant Lev Loktev.