A 12.7-mm Berezin BS modernized aircraft machine gun (factory number 1), USSR.

A 12.7-mm Berezin BS modernized aircraft machine gun (factory number 1), USSR.

The creation of the Air Force in the Soviet Union and the need to for the development of state-of-the-art warplanes also called for special aircraft machine guns. In the late1930s, M. E. Berezin, a weapon designer from Tula, managed to develop, with the assistance of the engineers A. T. Chepelev and Z. I. Mamontova from Central Design Bureau-14, an effective heavy aircraft machine gun.

Following factory tests in 1938-1939, the 12.7-mm Berezin synchronized aircraft machine gun was adopted for service in the Air Force before the completion of final factory tests. The same year, Kovrov Plant No.2 started manufacturing the Berezin BS.

In 1940, M. E. Berezin redesigned the weapon to make a versatile machine gun. The new 12.7-mm Berezin UB (Berezin's Universal) came in three versions: UBK (for the wings), UBS (synchronized), and UBT (for the turret), and could be mounted on warplanes and used in any mobile and stationary machine-gun systems.

During the Great Patriotic War, the Berezin UB, along with the ShKAS, became one of the main aircraft weapons used in mobile defense mounts of attack aircraft and bombers.

Characteristics:
Caliber, mm — 12.7
Length, mm — 1,455
Barrel length, mm — 410
Muzzle velocity, m/s — 814-850
Usable rate of fire, rpm — 700-800