BARREL CHANGE U.S. Navy Petty Officer 2nd Class Timothy Carter changes the barrel of an M240B machine gun during weapons training aboard the guided-missile cruiser USS Anzio, under way in the Red Sea, June 24, 2011. Carter, is a electronics technician. SHARE: Download: Full Size (0.08 MB) Credit: VIRIN: 951091-X-QSP36-106.jpg Photo Gallery