What caliber does the PKM use?

The PKM, which is a widely recognized general-purpose machine gun developed in the Soviet Union, uses the 7.62x54R caliber. This cartridge has been in use since the late 19th century and is known for its effectiveness at long ranges, contributing to the PKM's reputation for reliability and performance in various combat situations.

The choice of the 7.62x54R cartridge allows the PKM to achieve a good balance of power and trajectory, making it suitable for suppressive fire and engaging targets at a distance. The design of the PKM and its ammunition combination leads to its successful deployment in different terrains and combat scenarios, maintaining a significant role in various armed forces around the world.

The other calibers listed are used in different weapons systems. The 5.56x45mm is primarily associated with NATO rifles, the 7.62x39mm is famously used in the AK-47 platform, and the 5.45x39mm is associated with the AK-74 series. Each of these cartridges serves specific operational roles that differ from that of the PKM.