A Rail Gun is the primary armament of the United Nations Navy and Martian Congressional Republic Navy it is also called a Gauss Turret. The Donnager had rail guns at the beginning of the Series. It is unknown if other UNN or MCRN Cruisers, Frigates, etc. have rail guns excluding the Rocinante.
- A railgun uses the Lorentz Force, as in it will move perpendicularly or at a right angle with respect to the direction of the current path and magnetic field, to accelerate projectiles. The effect is initiated when a pair of electrically charged rails is bridged with an electroconductive material, like Tungsten for example .
- Current US Navy testing of Railguns employ Tungsten projectiles. Should the weapons be deployed, they will use Tungsten or Depleted Uranium projectiles.