Battle of Lake Khasan
The F-22 saw combat for the first time in the Battle of Lake Khasan in 1938. The gun was also used in the Winter War. On 1 June 1941 RKKA possessed 2,844 F-22s. Many were lost, but a limited number remained in service until the end of the war. For example, two artillery regiments (40 pieces) took part in the Battle of Kursk. It was mostly employed as a field gun, sometimes as anti-tank gun and was apparently never used as anti-aircraft weapon.