1833 vs 0331
Assault Amphibious Vehicle / Amphibious Combat Vehicle Crewmember (USMC) vs Machine Gunner (USMC)
Two Marines in the chow hall: one smells like the field, the other like hydraulic fluid. Both think they have it worse. Both are right.
Episode one of the documentary nobody commissioned but everyone needs: 1833, the Assault Amphibious Vehicle / Amphibious Combat Vehicle Crewmember. The AAV has been slated for replacement by the ACV (Amphibious Combat Vehicle) program, which means you may spend your contract transitioning between platforms. Episode two: 0331, the Machine Gunner. Those moments when the gun runs perfectly and the rounds are going exactly where you want them — that feeling is real and it costs you your lower back. The producer quit halfway through because "nobody would believe this is the same organization." The fact that this comparison exists is, itself, the kind of transparency the military hasn't figured out yet.
After the Uniform
The part the recruiter skips: what each job actually translates to once you're a civilian — and what it pays.
Salary data from the U.S. Bureau of Labor Statistics Occupational Employment and Wage Statistics program. A guide, not a guarantee.
Recruiter vs. Reality
The pitch versus what people who actually did the job report back.
“Crew the AAV-7A1 Assault Amphibious Vehicle, the Marine Corps' primary means of ship-to-shore amphibious assault. You'll be trained in water operations, vehicle gunnery, and the unique tactical requirements of amphibious warfare that makes the Marine Corps the only force capable of forced entry from the sea.”
The AAV-7 is a vehicle designed in the late 1960s and continuously fielded since 1972, which means you are operating a machine that was rolling off the assembly line when your parents were possibly not yet born. It is an aluminum-hulled, diesel-powered amphibious personnel carrier that carries Marines from ship to shore through surf that was not designed by anyone who cared about your comfort. It does not go fast in water. It does not go fast on land. It is, in the words of every AAV Marine who has ever loved one, "reliable." The maintenance requirements are substantial and the availability of legacy parts is an ongoing administrative challenge. The AAV has been slated for replacement by the ACV (Amphibious Combat Vehicle) program, which means you may spend your contract transitioning between platforms. The amphibious mission itself — that moment when the ramp drops and Marines hit the beach — is the most historically loaded event in the Marine Corps' identity. You are part of that lineage.
“Master the crew-served weapons systems that provide firepower superiority for Marine infantry units. Operate the M240B and M2 .50 caliber machine gun. Serve as the backbone of infantry squad automatic firepower in every combat environment.”
The M240 weighs 27.1 pounds. That is not counting the tripod, the T&E mechanism, the ammo, or the existential weight of knowing you are the most conspicuous target on any battlefield because your weapon sounds like the hand of God tearing fabric. You will carry all of this up things that should not be climbed, through things that should not be crossed, in temperatures that should not be experienced by humans. The M2 adds the additional joy of being crew-served by people who will argue for twenty minutes about headspace and timing before admitting they don't remember how to set it correctly. Maintenance on these systems is continuous and non-negotiable. Gunnery ranges are the bright spots. Those moments when the gun runs perfectly and the rounds are going exactly where you want them — that feeling is real and it costs you your lower back. SOI will prepare you for some of this. Nothing fully prepares you for the rest.
The Real Life
Same dimensions, side by side. 1833 on the left, 0331 on the right.
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Weapons maintenance, gun drills, range time, and infantry training. Machine gunners are integrated into rifle companies as weapons platoon members. You train to provide suppressive fire, establish engagement areas, and support the maneuver element. Garrison life mirrors standard infantry: PT, maintenance, cleaning, and field exercises.
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SOI (School of Infantry) at Camp Pendleton or Camp Geiger, followed by the Machine Gunners Course. You learn the M240B and M2 .50 caliber inside and out — assembly, disassembly, maintenance, ballistics, and employment. The course is physically demanding because you carry these heavy systems everywhere.
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Extreme. You carry the M240B (27 lbs) or M2 .50 cal (84 lbs for the system) plus ammunition, tripod, spare barrels, and your standard infantry load. Total pack weight regularly exceeds 100 lbs. Your shoulders, back, and knees will pay the price.
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Machine gunners are the backbone of the infantry weapons platoon and every rifle company commander wants a good one. The recruiter will tell you it's exciting — and putting rounds downrange with an M2 is genuinely thrilling. What they won't tell you: the weight is no joke. You carry the heaviest weapon system in the platoon on every hump, every patrol, every movement. The physical toll is severe and cumulative. Hearing damage and joint issues are practically guaranteed over a full enlistment. Promotion is as slow as any infantry MOS. The civilian translation is thin — the same challenge as all combat arms. But the discipline, teamwork, and mental toughness you develop are real, and the 0331 community has fierce pride. Just protect your ears and your joints.
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