Hard top HMMWVs, such as the HMMWV Armament Carrier with TOW missile configurations, have a roof hatch with a 360° rotating weapons ring. A gunner stands on a floor-mounted platform or rests on a web sling, partially exposed above the roof line of the HMMWV. A short pedestal mount is attached to the ring to support the pintle or pintle adaptor for all standard U.S. military machine guns (top photo).
USAF Airman Trevor Johnson mans a M249 5.56mm Squad Automatic Weapon (SAW) from the roof hatch of an M1043 HMMWV, Aviano Air Base, Pordenone, Italy, 20 November 2002. The HMMWV ring mount and post are visible but not in use.
High Mobility Multipurpose Wheeled Vehicle (HMMWV) Ring Mount
Many different mounting systems have been developed to utilize the basic roof hatch gunner arrangement, especially in response to the MOUT and counter-insurgency environment of Iraq and Afghanistan. Some have been standardized with nomenclature and NSNs while others are field expedients developed in-theater or in answer to field problem-solving requests. Some expedient solutions have later been standardized.
HMMWV Auxiliary Weapons Mount (HAWM)
HMMWV Eagle Mount and HAWM Secondary Weapon Mounts
By 2001, the Army was evaluating the Eagle Mount which allows gunners to mount a second weapon on the HMMWV ring mount, next to the primary weapon. It was used, for example, to mount an M249 5.56mm Squad Automatic Weapon (SAW) in addition to a TOW missile launcher on the HMMWV Armaments Carrier.
In 2004, the Eagle Mount became the HMMWV Auxiliary Weapons Mount (HAWM -- photo above). The U.S. Army Research Laboratory in Adelphi, MD developed the field bolt-on HAWM to attach to the roof gun ring to provide a second location where a weapon can be mounted. The 40-pound, wedge shaped cast steel platform is designed to be quickly installed or removed as the tactical situation warrants. The mount post is identical to the standard pintle post so all machine guns and the MK19 40mm Machine Gun can be mounted. By placing the second mount on the opposite side from the primary weapon, weight is evenly distributed and the turret ring turns easily. By December of 2004 these mounts were installed by units in Iraq including the 173rd Airborne Brigade and Maryland National Guard.
HMMWV Interchangeable Mount System (HIMS)
The HMMWV Interchangeable Mount System (HIMS) enables the unit to adapt to changes in the tactical situation quickly. With HIMS, the unit can quickly mount the MK19 40mm Machine Gun or the M2 .50 cal. Machine Gun on the HMMWV Armament Carrier and use them to destroy light armored vehicles, field fortifications, and troops.
The HMMWV Interchangeable Mount System (HIMS) is made up of two parts:
Part one is an armament mount panel assembly with pintle that mounts on the M1025 armament HMMWV carrier. This part is interchangeable with the missile guidance tray on the M966 TOW HMMWV carrier. The common turret ring of the two vehicles will accommodate the armament mount panel assembly using existing holes. No modifications are required.
Part two consists of a locally fabricated internal floor stowage plate that has automatic weapons stowage brackets, ammunition stowage trays, and footman tie-down straps already mounted for quicker emplacement. This plate is made of sheet aluminum and is mounted in the floor of the M966 TOW HMMWV carrier after removal of selected items of the TOW bracketry.
HIMS was distributed with a technical data package with instructions and parts lists.
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