US Navy 101025-N-6632S-056 The guided-missile cruiser USS Gettysburg (CG 64) fires its forward 5-inch Mark 45-54-caliber lightweight gun during a p

ATLANTIC OCEAN (Oct. 25, 2010) The guided-missile cruiser USS Gettysburg (CG 64) fires its forward 5-inch Mark 45/54-caliber lightweight gun during a pre-calibration firing exercise. Gettysburg is part of the George H.W. Bush Carrier Strike Group and is conducting training operations in the Atlantic Ocean. (U.S. Navy photo by Mass Communication Specialist Seaman Kevin J. Steinberg/Released)