Railguns use 20 to 32 mega joules of electromagnetic energy to fire projectiles at seven to nine times the speed of sound, according to a Congressional Research Service report on the weapons.
Because they fire with electricity alone — not chemical explosives like conventional ammunition — railguns can potentially operate much cheaper and fire much much faster than weapons currently used by the Navy.
The Navy has long sought the technology as a potential game-changer for surface warfare, as China, Russia, and the US all race towards building hypersonic weapons that no ship can currently defend against. The newest classes of Navy ships, like the Zumwalt and Ford carriers, have been planned with outsized power generators in anticipation of the revolutionary weapon.
Despite looking like a typical cannon blast, the railgun only emits fire and sparks from metal components that become molten during the firing process that forces the components to fire at mind boggling speeds.