|M1129 MC-B: General|
|Date of first acceptance||August 2005|
|Manufacturer||GM GDLS Defense Group, L.L.C.||Crew||
|M1129 MC-B: Dimensions|
|M1129 MC-B: Armament|
|7.62mm M240B MG||Commander's cupola||2,000 rounds||360°
|120mm Mortar RMS6-L||Passenger compartment||48 or 60 rounds||4400 mils
|1486 to 700 mils
|AN/VAS-5 thermal for driver|
|M1129 MC-B: Armor|
|High hard steel structure|
|M1129 MC-B: Automotive|
|Engine||Caterpillar 3126; 6-cylinder, 4-cycle inline turbocharged diesel|
|Transmission||Allison MD 3066P, 6 speeds forward, 1 reverse|
|Steering||Hydraulic, steering wheel|
|Brakes||Dual-circuit hydraulic with air-power assist; anti-lock system on rear 3 axles|
|M1129 MC-B: Suspension|
|Type||Road wheels||Shock absorbers|
|Hydropneumatic||4/side||On each wheel|
|M1129 MC-B: Performance|
|Max level road speed||60mph
|Max grade||60%||Max slideslope||30%|
|Max vertical obstacle||23"
|Min turning diameter||52'
|Max fording depth||51"
|Cruising range||~330mi, roads
There were two versions of the Stryker Mortar Carrier. The first, called MC-A, was very similar to the M1126 ICV. It was armed with the remote weapon system and could carry two mortars, which differed depending on which echelon the vehicle served. Battalion mortar platoons carried the 120mm mortar M121 and the 81mm mortar M252. Company mortar platoons carried the 60mm mortar M224 instead of the 81mm ordnance. Vehicles in RSTA squadrons only carried the 120mm mortar. The MC-A was unable to fire the mortars mounted; the crews were forced to dismount and emplace the mortars for use. The MC-A weighed 39,990lbs (18,140kg) loaded.
The MC-B was first fielded in late 2005. This vehicle is armed with the Recoiling Mortar System 6-L (RMS6-L) in the rear compartment. Based on the Israeli Soltam Cardom system, the RMS6-L uses the 120mm mortar M298 in a recoiling mount that cuts the recoil impulses by about 75%. Nonetheless, the suspension on the MC-B is strengthened over the suspension on normal Strykers to deal with firing the mortar from the vehicle. Similarly to the MC-A, MC-Bs in RSTA squadrons are armed solely with the 120mm mortar, while vehicles in battalion mortar platoons also carry a dismountable 81mm mortar M252 and those in company mortar platoons carry a dismountable 60mm M224 mortar instead of the 81mm ordnance. RSTA vehicles stow 60 120mm rounds, battalion vehicles carry 48 rounds 120mm and 35 rounds 81mm, and company vehicles carry 48 rounds 120mm and 77 rounds 60mm. The MC-B lacks the remote weapon system; the commander's station is instead ringed by a skate mount for a machine gun. The MC-B is not fitted with smoke grenade launchers. The rear side armor of the MC-B is vertical, and the passenger compartment is topped by two outward-opening hatches that allow the 120mm mortar to be fired from the vehicle. The secondary mortar baseplate is stowed on the rear of the right side of the vehicle.
The hull bottom was modified into a double-V shape beginning in 2010 in order to help mitigate the blast effect of mines and improvised explosive devices. The double-V hull (DVH) improvements also featured enhancements to the suspension system, wider tires, a height management system, and blast-resistant seating for the infantry squad. Further upgrades--including a 450hp engine; 60,000lb (27,000kg) suspension; 910-amp alternator; and an in-vehicle network--produced the Stryker A1 variant.