Crew-served weapon systems

The Army employs various crew-served weapons (so named because they are operated by two or more soldiers in order to transport items such as spare barrels, tripods, base plates, and extra ammunition) to provide heavy firepower at ranges exceeding that of individual weapons. The M240 is the Army's standard medium general-purpose machine gun. The M240 (left-hand feed) and M240C (right-hand feed) variants are used as coaxial machine guns on the M1 Abrams tank and the M2 Bradley IFV, respectively; the M240B is the infantry variant and can be fired from a bipod or tripod if carried by hand, or employed from a pintle mount atop a vehicle. The M2 .50-caliber machine gun has been in use since 1932 in a variety of roles from infantry support to air defense. The M2 is also the primary weapon on most Stryker ACV variants and the secondary weapon system on the M1 Abrams tank. The MK 19 40mm grenade machine gun is mainly used by motorized units, such as Stryker Brigades, HMMWV-mounted cavalry scouts, and Military Police. It is commonly employed in a complementary role to the M2.

The Army uses three types of mortar for indirect fire support when heavier artillery may not be appropriate or available. The smallest of these is the 60 mm M224, normally assigned at the infantry company level. At the next higher echelon, infantry battalions are typically supported by a section of 81 mm M252 mortars. The largest mortar in the Army's inventory is the 120 mm M120/M121, usually employed by mechanized battalions, Stryker units, and cavalry troops because its size and weight require it to be transported in a tracked carrier or towed behind a truck.

Vehicles

Main article: List of armoured fighting vehicles by country#United States
The U.S. Army was the first in the world to achieve 100% automotive mobility, and spends a sizable portion of its military budget to maintain a diverse inventory of vehicles. The U.S. Army maintains the highest vehicle-to-soldier ratio in the world.

The Army's most common vehicle is the HMMWV (High Mobility Multipurpose Wheeled Vehicle), which is capable of serving as a cargo/troop carrier, weapons platform, and ambulance, among many other roles.[23] The M1A2 Abrams is the Army's primary main battle tank, while the M2A3 Bradley is the standard infantry fighting vehicle.[25] Other vehicles include the M3A3 cavalry fighting vehicle, the Stryker,[26] and the M113 armored personnel carrier.