US Navy's 'Star Wars' weapon that can penetrate concrete 100 MILES away shown in public

Weapon uses speed rather than explosives to destroy its target and comes equipped with menacing Latin motto 'I, who am speed, eradicate' Warships can carry dozens of conventional missiles, costing around £600,000 each, but could be loaded with hundreds of railgun projectiles, at only £15,000 each Technology fires a shell weighing 10kg at up to 5,400mph over 100 miles A radical new weapon that can fire a shell at seven times the speed of sound has been shown off in public for the first time. The weapon was on display to the public for the first time at the Naval Future Force Science and Technology EXPO at the Walter E. Washington Convention Center in Washington, D.C. Scroll down for videos Using electromagnetic energy, the gun can fire a shell weighing 10kg at up to 5,400mph over 100 miles – with such force and accuracy it penetrates three concrete walls or six half-inch thick steel plates. Rear Admiral Matthew Klunder, head of US Naval Research, said the futuristic electromagnetic railgun – so called because it fires from two parallel rails – had already undergone extensive testing on land. Rear Admiral Matthew Klunder, head of US Naval Research, said the futuristic electromagnetic railgun – so called because it fires from two parallel rails – had already undergone extensive testing on land Admiral Klunder added: 'It will help us in air defence, it will help us in cruise missile defence, it will help us in ballistic missile defence … we're also talking about a gun that's going to shoot a projectile that's about one one-hundredth of the cost of an existing missile system today.