M1128 mobile gun system
Perhaps the most controversial member of the U.S. Army Stryker system, the 'M1128 mobile gun system is a self-propelled 105mm cannon intended to provide direct fire support to infantry. In Stryker units, it is complemented, for indirect fire, by the M1129 mortar carrier. Both systems are allocated both to the battalion and company levels.
The Mobile Gun System concept is increasingly seen as necessary, but there are criticisms that the Stryker version is an inferior substitute for the tracked M8 Buford (mobile gun system). One of the arguments against the M1128 is that its cannon is too heavy for a wheeled vehicle and it lacks protection, superior areas for the Buford, which had reached approval before it was defunded for budgetary reasons.
Stryker proponents argue that the logistics of the wheeled M1128 are superior to the tracked Buford, which required dedicated track mechanics.
Its M68A1E4 105mm cannon with muzzle brake is adapted from the main gun of the M60 Patton (tank), and can fire 18 rounds of 105mm main gun ammunition. The vehicle also has .50 and 7.62mm machine guns, as well as M6 smoke grenade launchers.