U.S. Marine Cpl. Chris P. Duane (right) receives assistance from an Romanian soldier in clearing a Russian RPK squad automatic rifle during the weapons familiarization phase of Exercise Rescue Eagle 2000 at Babadag Range, Romania, on July 15, 2000.

(U.S. Air Force photo by Tech. Sgt. David W. Richards)

This is Russia’s 50-year-old squad automatic weapon

With the adoption of the M27 Infantry Automatic Rifle by the United States Marine Corps, the Marines have replaced the M249 Squad Automatic Weapon.

What’s especially handy about the new M27 IAR is that it can use the same 30-round magazines used by M4 and M16 rifles. In fact, it looks very similar to the M4 and M16, too. Russia, though, has had a similar dynamic in operation for over five decades with the Ruchnoi Pulemyot Kalashnikova, often called the RPK for brevity’s sake.

The RPK replaced the RPD light machine gun in Soviet service starting in 1964. The original version fired the 7.62x39mm round used in the AK-47 assault rifle and the SKS carbine.

U.S. Marine Cpl. Chris P. Duane (right) receives assistance from an Romanian soldier in clearing a Russian RPK squad automatic rifle during the weapons familiarization phase of Exercise Rescue Eagle 2000 at Babadag Range, Romania, on July 15, 2000.

(U.S. Air Force photo by Tech. Sgt. David W. Richards)

The biggest difference between the RPK and the AK-47 is the length of the barrel. The AK-47’s barrel is about 16.34 inches long — the RPK’s barrel is about eight inches longer. Despite this, the RPK shares many common parts with the AK and can readily accept the 30-round magazines used by the assault rifle classic.