The US Navy has announced plans to deploy its first ever electromagnetic railgun, a “game changing” device that fires projectiles without explosives over a distance of 100 miles and at seven times the speed of sound.

Railguns use an electromagnetic force known as the Lorentz Force to rapidly accelerate projectiles between a pair of conductive rails, firing them at a velocity greater than can be achieved by traditional guns and artillery.

This increased velocity means that projectiles do not need to have any explosive payload. Instead, the railgun simply fires a solid lump of metal, relying on the speed of its impact to transfer massive amounts of heat and kinetic energy to the target.

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The Navy has said that weapon represents “the future of naval combat” with current prototypes capable of punching through the hull of ship “like a freight train” due to be installed and tested on ships by 2016.

“The American public has never seen it,” said Rear Admiral Matthew Klunder, chief of naval research, in a telephone press conference.

“Frankly, we think it might be the right time for them to know what we’ve been doing behind closed doors in a Star Wars fashion,” he said. “It’s now reality. It’s not science fiction. It’s real and you can look at it.”

Because railguns do not require any explosive shells, the price of firing the weapon is massively reduced, with a 10kg projectile costing just $25,000 -1/100th the cost of a conventional missile.

“I really think it will give our adversaries a huge moment of pause to go, ‘Do I even want to go engage a naval ship?’ Because you are going to lose. You can throw anything at us, and the fact that we can shoot a number of these rounds at very affordable costs - it’s my opinion that they don’t win,” said Klunder.

The technology for railguns was first proposed in the early 20 century but until now the cost of supplying the necessary electrical power has stopped the weapon from becoming practical.

The Navy has been developing the technology since 2005, with the team responsible adopting the latin motto of ‘Velocitas Eradico’, roughly translating as ‘I who am speed, eradicates’.