Navy fires their 32MJ Mach-8 railgun.
A tangle of two-inch thick coaxial cables hooked up to stacks of refrigerator-sized capacitors took five minutes to power juice into a gun the size of a schoolbus built in a warehouse. With a 1.5-million-ampere spark of light and a boom audible in a room 50 feet away, the bullet left the gun at a speed of Mach 8.
via Video: Navy’s Mach 8 Railgun Obliterates Record | Danger Room | Wired.com.