Defense Media Network

USMC Small Arms Developments

With the recent release of the fiscal year 2012 United States Marine Corps Posture Statement, Commandant of the Marine Corps Gen. James F. Amos points to four critical service priorities: continue to provide the best trained and equipped Marine units to Afghanistan; rebalance the Corps, posture it for the future, and aggressively experiment with and implement new capabilities and organizations; better educate and train Marines to succeed in distributed operations and increasingly complex environments; and keep faith with Marines, sailors, and families.

In one way or another, each of these priorities is affected by or has an impact on the myriad activities and developments surrounding the USMC small arms arena.

Representative examples of current and recent developments that help to balance service needs and priorities can be found across a wide range of Marine infantry company weapons systems, including rifles, pistols, machine guns, sighting systems, grenades/grenade launchers, rocket launchers, and new less-than-lethal concepts and systems.



U.S. Marine Corps Lance Cpl. Llyndun Cooper, serving with the 2nd Platoon, Lima Company, 3rd Battalion, 5th Marine Regiment, scans his surroundings through the scope of an M16A4 during a census patrol in the Sangin district of Helmand province, Afghanistan, Jan. 18, 2011. The unit, part of Regimental Combat Team 2, was conducting patrols to suppress enemy activity and develop relationships with residents of the area. U.S. Marine Corps photo by Lance Cpl. Dexter S. Saulisbury

Current Capabilities

The current service rifle for the USMC rifleman – Military Occupational Specialty Code 0311 – is the lightweight, air-cooled, gas-operated, magazine-fed, 5.56 mm M16A4. In addition, the weapon’s capabilities are supplemented by the M4 carbine and M4A1 carbine variants of the M16 family, with the carbine models assigned to Marines based on billet and mission requirements.

The current service pistols are the 9 mm M9 and M9A1.

The 40 mm M203 grenade launcher is a lightweight, single-shot, breech-loaded, shoulder-fired weapon that is attached to the M16 and carried by the fire team leader. Tactical applications are evident from the spectrum of current low-velocity 40 mm ammunition options that include: M651 chemical agent CS; M433 HEDP; M781 training practice; M661 green star parachute; M662 red star parachute; M713 red smoke ground marker; M715 green smoke ground marker; M716 yellow smoke ground marker; and M583/M583A1 white star parachute.

A relatively recent addition to Marine Corps small arms inventories is the M32 Multi-Shot Grenade Launcher, manufactured by Milkor USA, Inc. The M32 is a hand-held, semi-automatic, gas-operated, spring-assisted, 40 mm multi-shot grenade launcher with a revolving action. The cylinder-fed weapon with a six-round capacity is capable of firing all DODTI and NATO standard lethal and non-lethal 40×46 mm low-velocity munitions that have an overall length of 140 mm (5.5 inches) or less.

Machine gun firepower in the Marine Corps squad includes the 5.56 mm M249 Squad Automatic Weapon (SAW), a gas-operated, belt/magazine-fed, air-cooled, automatic weapon that is carried by the automatic rifleman and used to suppress targets at ranges up to 1,000 meters with rates of fire up to 850 rounds per minute.

Current program efforts are leading to the fielding of a new 5.56 mm M27 Infantry Automatic Rifle (IAR) to replace the M249 SAW within the infantry squad and light armored reconnaissance battalion. Credited in service descriptions as being “more durable, more accurate, and more reliable than the M249 SAW,” the IAR – also known as the Heckler & Koch 416 – began deliveries in 2011, with a scheduled full operational capability in 2012.

M32 Multi-Shot Grenade Launcher

U.S. Marines with Combat Logistics Battalion 6 (CLB-6), Combat Logistics Regiment 2, 2d Marine Logistics Group, conduct field operations training with an M32 Multi-Shot Grenade Launcher at Fort Bragg, N.C., on April 24, 2011. The field operation was to prepare CLB-6 for its upcoming deployment to Afghanistan in support of Operation Enduring Freedom. U.S. Marine Corps photo by LCpl William M. Kresse

Representatives at Marine Corps Systems Command (MCSC) note that some quantity of M249 SAWs will be retained at the Marine Corps company level.

The Marine Corps company is also supported by the 7.62 mm M240G medium machine gun. Resulting from a Marine Corps search for a machine gun that could fire at extended ranges and with greater dependability and accuracy than the older 7.62 mm M60E3, the M240G is a ground variant of the M240 machine gun found on the Marine Corps Light Armored Vehicle and M1 Abrams Main Battle Tank.

Tactical capabilities of the Marine Corps rifleman are also enhanced by several sighting/aiming systems.

The two cornerstones of the day optics program are the AN/PVQ-31A (for the M16A4) and the AN/PVQ-31B (for the M4/M4A1), the official Marine Corps designations for the Trijicon TA31RCOA4 series of sights known as Advanced Combat Optical Gunsight (ACOG). The rifle combat optics (RCO) give the Marine rifleman a fixed 4X optical aiming sight that attaches to a MIL-STD-1913 Rail Adapter System to provide a targeting tool to engage distant daylight and near low-lit targets with greater identification certainty.

According to service descriptions, “The RCO provides enhanced target identification and hit probability for the M4A1 and M16A4 rifle out to 800 meters. It incorporates dual illumination technology using a fiber-optic light source for daytime illumination and tritium for night and low-light use. This allows the operator to keep both eyes open while engaging targets and [maintaining] maximum situational awareness.”

In addition to the RCO, Marine Corps sources point to the SU-258/PVQ (Trijicon TA11SDO ACOG 3.5×35 w/RM05 Reflex) machine gun day optic (MDO) and the SU-258/PVG squad day optic (SDO) initiatives as rapid fielding solutions to provide a 6X day optic for the M240 series and a 3.5X day optic for the M249 series machine guns.

Incorporating dual illumination technology (fiber-optic light source for daytime illumination and tritium for night and low-light use), they provide enhanced target identification and hit probability for the M240G (to 1,000 meters) and M249 (to 800 meters) machine guns. The scopes also include miniature reflex sights to enhance engagements of close-range targets.

U.S. Marine Corps M4 Carbine

Marines with U.S. Marine Corps Forces, Pacific (MarForPac), conduct Table 3 Intermediate Combat Rifle Marksmanship Training with the M4 carbine May 5, 2011. MarForPac Marines began Table 3 qualifications in January as part of a Corps-wide effort to provide Marines additional weapons training. U.S. Marine Corps photo

The AN/PSQ-18A Grenade Launcher Day/Night Sight Mount (GLDNSM) also provides enhanced aiming capabilities/accuracy for the M203 grenade launcher.

Marine units downrange will also soon be fielding another new optic, known as the heavy day optic (HDO). HDO emerged in response to an April 2010 Urgent Statement of Need, which included endorsements from the commanding general of the 3rd Marine Division, III Marine Expeditionary Force, and U.S. Central Command.

According to subsequent Marine Corps documentation, the urgent need is based on the fact that “current combat operations are being conducted in all lighting conditions against combatants at extreme ranges. The M2 .50 caliber and Mk 19 Mod 3 [40 mm grenade launcher] have effective ranges in excess of 3,500 and 1,700 meters. However, the currently fielded iron, image intensified and thermal sighting system either offer limited detection ranges or do not enable the required employment methods, which are based largely on the need for range-corrected aiming points regardless of range, lighting condition, or sighting device.”

It adds, “The above limitations and shortcomings of legacy systems are squandering standoff and artificially limiting United States forces to iron sights; this creates a state of parity with the enemy and their technologically inferior small arms systems.”

Following a period of government market research, the solution to the urgent need was identified in the Leupold Mk 8 CQBSS (Close Quarter Battle Scout Sniper) optics, with a March 2011 contract award to Leupold & Stevens Inc. Although frequently characterized as sniper rifle optics, the new HDO will significantly enhance M2 and Mk 19 Mod 3 engagement capabilities for Marines in combat.

Along with the optical scopes and sights, Marine Corps riflemen can also employ the AN/PEQ-16A, a multifunction aiming laser device that emits visible or infrared (IR) light for precise weapon aiming, allowing rapid target acquisition and engagement. The device is also equipped with an integrated high-intensity, variable focus, white light illuminator that provides the shooter with the ability to illuminate selected areas.

In addition to rifles, pistols, and machine guns, Marine Corps anti-armor weapons include the M136/AT-4, a lightweight, self-contained, anti-armor weapon consisting of a free-flight, fin-stabilized, 84 mm rocket in a single-shot disposable cartridge, and the M72A7, a lightweight, self-contained, anti-armor weapon that can be fired from either shoulder.

M249 Squad Automatic Weapon

Lance Cpl. Marcus Terry, an infantryman assigned to the Ground Combat Element, Marine Barracks Washington, fires the M249 Squad Automatic Weapon through a mock window on an unknown distance course at Marine Corps Base Quantico, Va., May 18, 2011. U.S. Marine Corps photo by Sgt. Bobby J. Yarbrough

Current Marine Corps rifleman munitions also include the M18A1 Claymore mine, an anti-personnel mine consisting of 1.5 pounds of C-4 and approximately 700 steel ball bearings, and the M67 fragmentation grenade.


Near Term

MCSC representatives point to some near-term development activities that will soon facilitate company-level actions.

One example can be found in the M224A1 lightweight company mortar. The new design, which reduces the weight of the mortar, bipod, and base plate combination by 20.34 percent, will begin fielding in the fourth quarter of FY 11.

Another recent small arms development involves the .45-caliber M45 Close Quarter Battle Pistol (CQBP). Characterized as “[M]1911 style” by service representatives, the CQBP will serve as the backup weapon for reconnaissance Marines and Marines serving in Marine Special Operations Command.

Slightly further along the pipeline are efforts to produce a lightweight battalion mortar to replace the current 81 mm mortar system, which could reduce the weight of the current system by 25 percent.

Another example is the next-generation Shoulder-launched Multipurpose Assault Weapon (SMAW II). Currently in the Engineering and Manufacturing Development phase, the SMAW II launcher is scheduled to begin fielding in late FY 12.

Marine Corps combat developers have also actively participated in the Joint Integrated Product Team that developed Individual Carbine (IC) requirements being enunciated by the U.S. Army.

Marine Corps sources note that they will closely monitor IC progress and, in parallel with that effort, add that the Marine Corps “is developing a path forward to optimize the M16A4 and M4 carbine with significant product improvements in the event the IC is not selected to replace the Marine Corps Modular Weapon Systems (M16A4 and M4).  We are closely aligned with [the] U.S. Army’s planned improvements to the M4. These improvements are designed to enhance performance, reliability, and sustainability.”

One representative example of a possible product improvement for optimizing the M16A4 emerged in a late 2010 “sources sought” announcement in which the MCSC program manager for Optics Systems requested “information on production of a Grenade Launcher Sight System.” The request for information called for white paper responses as to how potential commercial off-the-shelf/commercial and/or non-developmental items could meet a range of threshold (T) and objective (O) performance attributes including: mountable for operational use to the M16A4, M4, M4A1 (T), and M32A1 (O); attachable to MIL-STD-1913 rail (T), NATO Rail as defined by STANAG 4694 (O); allow for ambidextrous operation when mounted; cause less weapon imbalance than AN/PSQ-18A (T = O); high-angle capability to enable the user to accurately engage targets from 30 meters to 100 meters with a high-angle (indirect fire) solution using M433 40 mm HEDP and an M203 (T) or M32A1 (O); low-angle capability to enable the user to accurately engage targets from 100 meters to 400 meters with a low-angle (direct fire) solution using M433 40 mm HEDP and an M203 (T) or M32A1 (O); provide a day aiming capability for high- and low-angle engagements without the use of an electric power source (T = O); provide a night aiming capability for high- and low-angle engagements (T = O); enable the user to accurately engage targets at elevations above and below the user (O); determine range to target (O); weight in operational configuration no more than 17.7 ounces (T) and 8 ounces (O); and compatibility with all current low-velocity 40 mm ammunition (T = O).


M-45 Close Quarters Combat Pistol

A round from an M45 Close Quarters Combat Pistol leaves the barrel during combat marksmanship training aboard Camp Lejeune, N.C., Nov. 3, 2010. MARSOC critical skills operators continuously sharpen their marksmanship skills for future operations. U.S. Marine Corps photo by Lance Cpl. Thomas W. Provost

Less than Lethal

Reflective of the Marine Corps priorities for posturing for the future and experimenting and implementing new capabilities, MCSC is also procuring and exploring a range of non-lethal/less-than-lethal small arms capabilities.

One example appeared in the recent sole source contract award from MCSC PG-13 (Infantry Weapons Systems Directorate Program Manager for Non-Lethal Systems) to Combined Systems, Inc. (CSI) for the procurement of 40 mm flash-bang/smoke combination ammunition cartridges for day/night operations. The cartridges correspond with the VENOM™ Non-Lethal/Tube Launched Munition System (NL/TLMS). The three-bank launching system (10 rounds each) is used in crowd control operations.

Although service efforts have targeted development of a tube-launched non-lethal Mission Payload Module (MPM) system to control crowds, deny/defend areas, control access, and provide longer range, greater area coverage, extended duration, and better scalability of effects than the current NL/TLMS, program documents note that the MPM is not slated for fielding until FY 14.

Another ongoing development from MCSC PG-13 can be seen in the April 2011 announcement for an industry conference on a possible ocular interruption system. According to the announcement, the command has interest in a commercial off-the-shelf, commercial, or non-developmental item with minimal development system that can be both weapon-mounted and hand-held and would provide an “inherently eye-safe” glare effect/visual degradation that could be employed in selected situations.

According to the announcement, “Human effects range from very low visual degradation through high level visual degradation (dependent upon irradiance level). A very low-level of visual degradation is consistent with accomplishing the task of a visual warning, while achieving low through high levels of visual degradation is consistent with accomplishing the task of visual suppression.”

This article first appeared in Marine Corps Outlook: 2011-2012 Edition.


Scott Gourley is a former U.S. Army officer and the author of more than 1,500...