

GEAR 1 Hybrid Close Combat Vehicle Light (two Variants)
The hull and powertrain of the fusion-electric drive powered HCCV-L are based on a design which found its way into a separate successful Unmanned Ground Vehicle design, the RMGS (Robotic Mobile Gun System) Mark 1.
Compared to the RMGS Mk. 1, the hull has seven standard metal alloy road wheels like a traditional tank, where on the HCCV-L, the five main road wheels were replaced by a new composite design incorporating an alloy core and a flexible tire-like structure, plus a highly-sprung suspension. Combining the suspension and the natural malleability of the Kevlar and alloy mesh layered "tires", the HCCV-L has both high speed and improved cross country performance.
The experimental HCCV-L was fitted with a surplus M1A2G1 Abrams main battle tank turret, incorporating a next-generation "squeezebore" kinetic energy weapon. The standard M256, 120mm barrel was lined with a thermoresistant layer and 40mm barrel for the smaller-caliber KE penetrator dart. It fires darts encased in a highly efficient, fully-consumed explosive propellant, and can defeat all conventional armor except the advanced composite armor of the M1A2G1 and other GEAR 1 combat vehicles at ranges of up to 4 miles.
The production HCCV-L still uses a turret shape derived from the M1A2G1, replacing the 120mm M256 gun with a 150mm Squeezebore Railgun. It fires a three-inch (76.2mm) kinetic energy penetrator dart or high explosive "molten metal" thermo-kinetic armor penetrator out to six miles. The muzzle velocity of the round and flight accuracy is achieved with a long barrel and the railgun coil inside the thick lining which fires a directed energy pulse to accelerate the round after burning the propellant.
The Squeezebore and Squeezebore-Railgun weapons systems are highly experimental, providing features such as increased range and accuracy, plus highly improved fire on the move capability due to very low recoil, but it is assumed that successful fielding of the RMGS/HCCV-L automotive components and hull will continue independent of the development of the primary turret weapons, allowing the fitment of multiple turret and weapon options to the lighter, faster vehicle. Plans for the armed forces include transitioning the Armored Cavalry and select rapid movement units with the HCCV-L platform in their TO&E in place of traditional tanks and cavalry fighting vehicles. Some units may reduce manpower and trade their manned mounts for RMGS Mark 1 UGV's.

(A Remote Mobile Gun System Mark 1 Unmanned Ground Vehicle with the same 105mm gun armament as the G1127 "Stryker" Mobile Gun System and other GEAR 1 platforms, shown rigged for transport by rail.)