A warning siren bellowed through the concrete bunker of a top-secret Naval facility where U.S. military engineers prepared to demonstrate a weapon for which there is little defense.
Officials huddled at a video screen for a first look at a deadly new supergun that can fire a 25-pound projectile through seven steel plates and leave a 5-inch hole.
The weapon is called a railgun and requires neither gunpowder nor explosive. It is powered by electromagnetic rails that accelerate a hardened projectile to staggering velocity—a battlefield meteorite with the power to one day transform military strategy, say supporters, and keep the U.S. ahead of advancing Russian and Chinese weaponry.
