0331 -  Machine Gunner

             Pvt- Sgt

The 0331 Machine Gunner is the primary MOS for enlisted infantry Marines who operate man portable medium and heavy machineguns as part of the Infantry Battalions' weapons platoons and companies.

The Machine Gunner is responsible for the tactical employment of the 7.62 mm Medium Machine-Gun, the 50 cal., and 40mm Heavy Machine-Gun, and their support vehicle. Machine Gunners provide direct fire in support of the Infantry Rifle squads/platoons/companies. They are located in the weapons platoons of the rifle and weapons company in the infantry battalion. Noncommissioned Officers are assigned as team leaders and squad leaders/section leaders.

Marines will enter this MOS as an entry level MOS and be designated by the MOS 0300.  After they graduate Basic Infantry Marine Course, Infantry Training Battalion, School Of Infantry, Camp Pendleton, California or Camp Lejeune, North Carolina, they will move onto machine gun training. Machine Gunners earn their MOS after they complete the Machine Gunner Course at School Of Infantry, Camp Pendleton, California or Camp Lejeune, NC.


Team/Squad Leaders will complete the Advanced Machinegun Course at School Of Infantry, Camp Pendleton, California Camp Lejeune, North Carolina.


Squad/Section Leaders will complete the Infantry Squad Unit Leaders Course  at School Of Infantry, Camp Pendleton, California Camp Lejeune, North Carolina.

0331's will become proficient with the M240B Medium Machine Gun, the Mk19MOD3 40mm Automatic Grenade Launcher, and the M2 Browning .50 Caliber heavy machine gun.

To learn more about enlisted career paths, please visit our Enlisted Info section.

To learn more about other MOS's, please visit our Complete MOS List.

If you feel any of this information is inaccurate or incorrect, or have additional resources to inform our audience, please Contact Us.

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