What Guns and Rifles Do Marine Snipers Use? A Guide to U.S. Marine Sniper Weapons

Marine snipers use rifles selected for different distances, missions, and target types—not one universal weapon. The Marine Corps’ modern precision-rifle inventory includes the bolt-action Mk 22 Advanced Sniper Rifle, the Mk 13 Mod 7, and the semi-automatic M110 family. Older rifles such as the M40 remain important to the Corps’ history, while the M38 is a designated marksman rifle rather than a traditional sniper rifle. Understanding those distinctions helps explain how Marine precision teams choose their equipment.

The M110 is a semiautomatic 7.62×51mm NATO rifle in the broader family of precision rifles used by U.S. forces. The Marine Corps has fielded M110 variants for precision roles. Semiautomatic operation allows a shooter to fire follow-up shots without manually cycling a bolt, which can be useful when a situation calls for quicker engagements or multiple precise shots.

That does not make the M110 interchangeable with a bolt-action rifle in every respect. The systems differ in design, handling, and intended employment. A semiautomatic rifle may be selected where follow-up speed and flexibility are priorities, while a bolt-action rifle may be selected for a different precision requirement. The specific configuration and optics can also vary.

The M110 should not be confused with the M38 Squad Designated Marksman Rifle simply because both are semiautomatic and use 7.62mm ammunition in some configurations. They are distinct systems with separate names and roles. Nor should every rifle described as an “M110” be assumed to have identical components; military versions and upgrades can differ.

M40: The Marine Corps’ Historic Sniper Rifle

The M40 series is one of the best-known Marine sniper rifle families. It began in the Vietnam era as a Marine adaptation of the Remington 700 bolt-action rifle and evolved through multiple versions, including the M40A1, M40A3, M40A5, and M40A6. The series was chambered in 7.62×51mm NATO and served for decades.

Successive M40 upgrades addressed stocks, optics, suppressors, and other components. The M40A6, for example, incorporated a folding-stock chassis. These changes reflect a recurring feature of military procurement: a rifle can remain recognizable while its configuration changes significantly over time.

The M40 is now best understood as a legacy Marine sniper rifle, not a single answer to what every Marine sniper carries today. It remains relevant in historical accounts and discussions of Marine precision shooting, but newer systems such as the Mk 13 Mod 7 and Mk 22 represent later modernization efforts.

M38 Squad Designated Marksman Rifle

The M38 is a Marine Corps Squad Designated Marksman Rifle, or SDMR, based on the M27 Infantry Automatic Rifle platform. It is intended to give a squad an enhanced precision capability beyond that of a standard service rifle. The M38 uses 5.56×45mm NATO ammunition and is fitted with a higher-magnification optic than a typical close-combat rifle setup.

The M38 is often mentioned in online lists of Marine sniper rifles, but its designation matters. A designated marksman supports a squad’s precision needs; that role is different from a traditional scout sniper assignment. The M38 is not simply a shorter-range version of the Mk 22. Its cartridge, platform, and place within the unit are different.

Likewise, a Marine trained to use a precision rifle is not automatically a scout sniper. Weapons are assigned according to role, training, and unit requirements. The distinction prevents a common mix-up between “sniper rifle” as a broad casual label and specific military equipment categories.

M107 and Other Large-Caliber Rifles

The M107 is a semiautomatic .50-caliber rifle derived from the Barrett M82 family. Marine units have used it for specialized applications, including engaging equipment and other materiel targets at extended distances. It is substantially heavier and uses much larger ammunition than standard sniper rifles, so it is not a general-purpose replacement for the Mk 22 or M110.

The term “anti-materiel rifle” describes the M107’s specialized emphasis. Although it can be used in precision shooting, its .50 BMG cartridge and size make its role distinct from the conventional anti-personnel sniper rifles commonly associated with Marine precision teams. Public references sometimes call it a sniper rifle because of its long-range precision capability, but that label alone does not explain its intended employment.

Older Marine precision systems may also appear in historical sources, including the M14-based Designated Marksman Rifle and Mk 12 Special Purpose Rifle. Such references should not be taken as proof that those weapons remain standard issue across today’s Marine sniper units. Equipment status changes, and public sources may describe a particular era or a limited application.

How Marine Snipers Choose a Rifle

A rifle selection depends on the mission, target, distance, available ammunition, and operating environment. Military teams also consider weight, reliability, optic choice, suppressor compatibility, and how the weapon fits with the rest of the team’s equipment. A system that works well for one assignment may be less suitable for another.

• Action type: Bolt-action rifles support deliberate precision fire; semiautomatic rifles make follow-up shots faster.
• Cartridge: Ammunition affects trajectory, recoil, availability, and the rifle’s intended role.
• Optics: The sighting system is an essential part of a precision rifle package, not an optional detail.
• Modularity: Systems such as the Mk 22 can be configured for different requirements, subject to approved components and training.
• Unit role: A scout sniper, designated marksman, and anti-materiel rifle operator do not necessarily use the same equipment.

These factors explain why a list of weapon names cannot capture every detail of Marine sniper capability. The rifle is part of a larger system involving ammunition, observation equipment, communications, training, and team procedures.

Marine Scout Snipers and Changes in the Force

Marine Corps sniper weapons are also discussed in the context of changes to scout sniper organization. In 2023, the Corps announced that it would disband its Scout Sniper Platoons and change how it develops and employs precision-shooting capabilities. The announcement concerned force organization and training, not the immediate disappearance of precision rifles from Marine service.

That distinction matters when interpreting current information. A Marine unit can retain precision weapons and trained personnel even as the Corps adjusts occupational structures, course pipelines, or the way capabilities are organized. News about scout sniper platoons should not be read as evidence that the Marine Corps no longer uses sniper rifles.

How to Verify Current Marine Sniper Rifle Information

For the most reliable picture, readers should compare a rifle’s official designation with the source’s publication date and context. Marine Corps and Department of Defense releases can confirm procurement or fielding milestones, while older articles may describe weapons that have since been replaced or modified. Manufacturer pages can explain a rifle’s commercial design, but they do not independently prove how widely the military fields it.

Useful sources include Marine Corps news releases, Defense Department procurement announcements, and official program documentation. Search terms such as “Marine Corps Mk 22 Advanced Sniper Rifle,” “Mk 13 Mod 7 Marines,” and “M38 Squad Designated Marksman Rifle” can help separate current systems from historic ones. In short, Marine snipers have used several rifles over time, but the Mk 22, Mk 13, and M110 family are among the most relevant modern systems, with the M38 and M107 serving distinct precision roles.