PU-21

Russian (at the time Soviet) military forces have not fielded a squad-level, intermediate caliber, belt-fed machine gun since the retirement of the RPD in the early 1960s.^[1]

Official Soviet doctrine from the 1960s onward dictated that squad-level suppressive fire would be provided by the RPK, while PK machine guns would be issued at the company level to provide heavier fire.^[2]

The Soviet military moved from the 7.62×39 mm round to the 5.45×39 mm cartridge for its rifles and light machine guns.

Therefore, it considered adopting a dual-feed light machine gun in the new caliber to replace the RPK, similar to the FN Minimi in Western armies.

This resulted in the development of the PU-21 light machine gun.

The PU-21 can be fed from either a 45-round magazine or a 200-round belt. Its sights are graduated to distance of 1,000 metres (3,300 ft).^[3][4]

The PU-21 prototypes were thoroughly tested by the Soviet Army in Leningrad, but military experts did not see convincing arguments for replacing the RPK and RPK-74 with the PU-21 design.^[5]

According to the Soviet military, the design was too complex compared to other weapons then in service, and failed to enhance combat effectiveness.^[6][7]

The PKM machine gun, the modernised PK variant, was adopted instead.^[8]

• List of machine guns
• List of dual-feed firearms
• Ares Shrike 5.56
• RPK-74
• RPL-20, a similarly belted 5.45 machine gun, drew some inspiration from this project
• PKM
• FN Minimi
• QJY-88
• List of Russian weaponry