The key to the Marine Corps’ success and its most basic element is the Marine rifleman. A tough, tenacious warrior that the German soldiers of World War II found to be so ferocious that they gave him the nickname “Teufel-hunden” or Devil Dog. The Marine rifleman is an extremely effective and efficient killing machine on the battlefield.
One of the tools that make Marines so effective is the weapons with which they’re armed. The standard fire team is made of four Marines armed with three M4 or M16 rifles (the fire team leader carries an M203 40mm grenade launcher) and an M249 SAW (squad automatic weapon). This configuration of men and weapons has served the Marine Corps well for nearly 20 years, but in recent years, and especially with the greatly increased operational tempo, the time has come for an update. The biggest impetus for this evolution has been the change from Cold War-style massed infantry tactics, where a heavy base of fire from a SAW would allow the fire team to operate and maneuver in the open environments of Eastern Europe, to a more fluid CQB (close quarters battle) unit in urban Iraq.
Another consideration is the current fighting environment. When the M249 is in condition 1 (bolt charged to the rear, locked, and ready to fire), the chamber and feed area is open to sand, dirt, and debris. A further detriment to the combat longevity of the SAW gunner is the weapon’s profile. The fact that it is easily recognizable as a belt-fed, light machinegun makes the SAW gunner a high-priority target for enemy snipers hoping to eliminate the fire team’s most casualty-producing weapon. With a large carrier for the cartridge belt hanging beneath the weapon and a bipod off the gas block, it is markedly different from what the other fire team members are carrying.
Another consideration for reconfiguring the fire team is that, with its open-bolt and belt-fed operation, the SAW has a reduced probability of first-round ignition over something like a closed-bolt, magazine-fed M16. With a round chambered and locked in an M16, the trigger mechanism simply has to release the hammer and strike the primer causing the chambered round to fire. This gives better than 99 percent first round ignition probability, a must-have when patrolling or clearing a building. With a belt-fed machine gun the cartridge must be stripped from the metal link, fed into the chamber, and the bolt locked into the barrel extension. This presents a higher potential for a first-round malfunction, meaning that in house-to-house fighting, the SAW gunner can never be the first man through a door.