<P> A railgun is a device that uses electromagnetic force to launch high velocity projectiles, by means of a sliding armature that is accelerated along a pair of conductive rails . It is typically constructed as a weapon, and the projectile normally does not contain explosives, relying on the projectile's high speed to inflict damage . The railgun uses a pair of parallel conductors, or rails, along which a sliding armature is accelerated by the electromagnetic effects of a current that flows down one rail, into the armature and then back along the other rail . It is based on principles similar to those of the homopolar motor . </P> <P> As of 2018, railguns were being researched as weapons that use electromagnetic forces to impart a very high kinetic energy to a projectile (e.g. APFSDS) rather than using conventional propellants . While explosive - powered military guns cannot readily achieve a muzzle velocity of more than about 2 km / s, railguns can readily exceed 3 km / s . For a similar projectile, the range of railguns may exceed that of conventional guns . The destructive force of a projectile depends on its kinetic energy at the point of impact and due to the potentially large velocity of a railgun launched projectile their destructive force may be much greater than conventionally launched projectiles of the same size . The absence of explosive propellants or warheads to store and handle, as well as the low cost of projectiles compared to conventional weaponry, come as additional advantages . </P>

What is a railgun and how does it work