The railgun, a futuristic electromagnetic weapon that can fire a projectile at seven times the speed of sound, made its public debut at the the U.S. Navy's Science and Technology Expo. (Reuters) 
 
 First it mounted a laser aboard a ship in the Persian Gulf. Now the Navy has publicly unveiled another futuristic weapon: the electromagnetic “rail gun.” 
 
 In development for years, the weapon would be able to fire a projectile at Mach 7, or seven times the speed of sound, hitting targets 110 miles away. (By comparison, a Hellfire missile travels a little over Mach 1.) 
 
 Instead of gunpowder as a propellant, it uses electromagnetic pulses, and the projectiles hit with such overwhelming force that they don’t need to be armed with explosives. The impact from traveling at such amazing speeds is enough, thank you very much. Lasers sizzle rather than go boom, as some have said. The rail gun definitely has one heck of a boom. 
 
 The gun made its debut at the Navy’s Future Force Science and Technology Expo at the Washington Convention Center this week. 
 
 One top Navy official recently likened the impact to “a freight train going through the wall at a hundred miles an hour.” The lack of gunpowder and explosive warheads eliminates some significant safety hazards for Navy crews, officials say. 
 
 By the way, here’s video of that laser: 
 
 The Navy is unveiling a laser weapons capability that can be used aboard ships at sea. (U.S. Navy) 
 
 [RELATED: With photos and video, Navy shows how its new laser gun works at sea] ||||| The Navy and Marine Corps’ new ‘Star Wars’-style weapon made its debut in the nation’s capital this week. 
 
 The Electromagnetic Railgun, developed by the Office of Naval Research (ONR) with BAE Systems, has the potential to revolutionize naval warfare. 
 
 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. Wednesday and Thursday. The biennial event showcases the latest advances in power projection and force protection, including this year’s star - the EM Railgun. 
 
 To defend ships, conduct surface warfare against enemy vessels and support U.S. Marines and ground forces, EM Railgun-armed ships will be able to fire hypervelocity projectiles giving US forces even greater reach and lethality. 
 
 The EM Railgun is one immensely powerful weapon. 
 
 How does it work? 
 
 The EM Railgun launcher is a long-range weapon that uses electromagnetic energy, instead of conventional chemical propellants, to fire projectiles. 
 
 The ship generates electricity and this electricity is stored over several seconds in the pulsed power system and an electric pulse is sent to the railgun. 
 
 It gets its name from its use of rails. High electrical currents accelerate a sliding metal conductor between two rails and this creates magnetic fields to launch projectiles. 
 
 The electromagnetic force is so powerful that it launches the projectile up to Mach 6, firing projectiles farther and faster than current options. These projectiles reach an amazing 4,500 mph and precisely hit targets more than 100 miles away. 
 
 Mach 6 is more than six times the speed of sound. 
 
 To put how fast that is in context, Lockheed Martin’s Skunk Works has built the fastest manned airplane, the Blackbird, and that flies around Mach 3. 
 
 Once launched, the projectile uses its extreme speed, the kinetic energy, rather than conventional explosives to destroy targets on land, at sea or in the air. 
 
 And to put the improved distance in perspective, the current Mk 45 naval gun mount has a range of about 13 nautical miles with conventional ammunition. 
 
 What does it fire? 
 
 With ONR, BAE Systems is developing the next-generation HVP, Hyper Velocity Projectile, that can be fired by the EM Railgun and future models of railguns. 
 
 The HVP will also be compatible with current weapons systems like the Navy 5-Inch Mk 45, and Navy, Marine Corps, and Army 155-mm Tube Artillery systems. 
 
 It’s designed to be a guided projectile with low drag for high-velocity, maneuverability and decreased time-to-target. It has advanced guidance electronics and in flight, the HVP will be 24 inches long and weigh 28 pounds. The ammunition will be easy to handle and transport. 
 
 The Navy’s EM Railgun will fire 10 of these rounds per minute. When fired with an Mk 45 the HVP will be 20 rounds per minute and extend range to 50 nautical miles. 
 
 What are the advantages? 
 
 Railguns are a smart alternative to current large artillery and this weapon represents significant advances in U.S. Navy and Marine Corps capabilities. 
 
 It also provides additional benefits like enhancing safety aboard surface ships while greatly reducing cost. 
 
 Since this system that does not use gunpowder or propellant to fire the projectile, it reduces the need for high explosives to be carried on ships and the related hazards in doing so. 
 
 Off the ship, the EM Railgun will improve safety as well. Since it uses its extreme speed on impact, the danger of unexploded ordnance on the battlefield will be reduced. 
 
 Another key advantage is cost. Railgun projectiles are a mere fraction of the cost of those currently used in missile engagements – possibly even one percent of the cost of today’s missile systems. 
 
 Achieving this “Star Wars” - style weapon has not been easy. For years, many programs have sought to build such a powerful weapon, but a design that works, and works on a practical level, has been incredibly difficult to crack. Generating the power necessary to accelerate rail gun projectiles and creating materials capable of resisting the extreme temperatures generated are just two of the enormous obstacles a successful railgun needs to overcome. 
 
 Development of ONR’s Electromagnetic Railgun began about ten years ago. Phase I focused on developing the launcher, pulsed power, and risk reduction for the projectile. In 2012, Phase II began further advancing the technology, such as a firing rate of 10 rounds per minute. 
 
 What’s next? 
 
 The railgun program continues to perform impressively and is on track for its scheduled at-sea testing next year. 
 
 Ballet dancer turned defense specialist Allison Barrie has traveled around the world covering the military, terrorism, weapons advancements and life on the front line. You can reach her at wargames@foxnews.com or follow her on Twitter @Allison_Barrie.
– The Navy's latest weapon is an electromagnetic "railgun" designed to fire projectiles fast and far without using gunpowder as a propellant, the Washington Post reports. Unveiled at a Navy expo this week, the weapon uses electromagnetic impulses to shoot projectiles at up to seven times the speed of sound, creating a force so powerful that no explosive warheads are needed. The impact is like "a freight train going through a wall at a hundred miles an hour," says a top Navy official. It's also far cheaper than other missile engagement systems, and should reduce risk on surface ships because explosives aren't required, Fox News reports. How it works: The railgun draws electricity from a ship and fires projectiles using electromagnetic energy. Under the hood, a sliding metal conductor accelerated by an electrical current runs along the weapon's two metal rails, charging up magnetic fields that fire projectiles. But the gun requires 34 mega joules of power to launch a single 23-pound projectile more than 100 miles at Mach 7, and most destroyers don't have that kind of power in reserve yet, the Navy Times reports. What's more, engineers will need months or even years to link the railgun to the combat system on cruisers and destroyers. The Navy plans to give the weapon its first sea-test next year. The Navy's other cool new toy is a laser that it fired from a vessel for the first time in December.