Navy fires up fully-weaponized railgun prototype At the end of last month, the Navy got an early Valentine's Day present in the form of a prototype fully-weaponized naval railgun. And on Tuesday, it released a video of its first shot, which we're officially filing under "things not to get in the way of." This prototype weapon, developed by BAE Systems, fires inert aluminum slugs out of a 40-foot barrel using nothing but megajoules of raw electricity. The giant gout of flame you see in the picture (below) comes from a combination of about a million amps of energy, the hypersonic...