Mark 2 Railgun
The Mark 2 Mod. 0 Special Applications Scoped Railgun is a long-range man-portable, shoulder-fired anti-materiel railgun designed as a lightweight, skeletonized successor to the battle-proven Mark 1 Railgun. It is chambered for special 25mm saboted depleted uranium alloy rounds and, despite a projectile weight measuring in at twice that of the 12.7mm Mark 1 rounds, propels them at similarly hypersonic velocities.
The Mark 2 is no longer than the Mark 1, measuring in at 1.24 meters long to the Mark 1's 1.26, and weighs considerably less at 16.7 pounds to the Mark 1's 28.9. It is capable of breaking down into two halves for simpler storage by means of a rotating carrying handle, similar to that of a machine gun, and the breech assembly is mated to the rails, featuring a side-loading gate with dust cover instead of the break-action breech of the Mark 1. This ensures that the optic, typically a robust high-power variable optic, is not only aligned with the rails, but does not come out of alignment after successive shots or reloads which may offset the point of aim from the rails. The rails themselves are a higher-efficiency design, placed in a side-by-side fashion instead of over-under. The top is open, with vents and shields along the sides, which allows for significantly reduced weight at the cost of more severe muzzle flash and blast directed upwards.
The Mark 1's externally-mounted powerpack is retained, for ease of development, although it now lacks any powerpack-mounted external switches. Ergonomics and fire controls have been improved to the point where a single ambidextrous fire selector, located above the pistol grip to allow for easy thumb access, controls the charge, reset, and safety. When set to fire, the rails are charged and "live", and a simple trigger pull will fire a round. The rails will retain charge after firing, and only setting the weapon to safe will discharge them.
The stock is a heavily modified, skeletonized Mark 1 stock, featuring enhanced recoil buffer systems, an integrated adjustable monopod, and cheek riser. Despite being significantly lighter and smaller than the Mark 1's stock, it is still about as comfortable and severely reduces felt recoil.
The Mark 2 also incorporates several design elements from the highly successful Mark 15 Adaptive Rifle System, including the adjustable match-grade trigger and modular rail system. An integrated magnetic rail on top of the breech allows for mounting of most, if not, all, high-power optics, while a modular rail system on the bottom allows for end-user customization with regards to bipods, grips, or other attachments in order to save weight.
The newest version of standard ammunition used in the Mark 2 is a 25mm depleted uranium/tritanium alloy slug encased in a weighted ferro-nickel alloy cup sabot, which weighs more than the projectile. When fired, the sabot is propelled at hypersonic velocity (>Mach 9.8), carrying the projectile with it towards the target. This impacts a target with a significant amount of kinetic energy, almost twice that of an M829A4 APFSDS round fired from the 120mm main gun of an M1A2 Abrams.
A shortened rail assembly is in the works, designed to fire low-velocity ferro-nickel alloy-encased projectiles with explosive or HEAT fillers. This is designated as the Mark 2 Mod. 1 Rail Assembly Kit (RAK) and will be issued for shipboard fighting.