Airmen collect expended brass shell casings after firing an M-4 Carbine at the Combat Arms Training Range, July 9, 2013, Eielson Air Force Base, Alaska. Prior to shooting live ammunition, airmen practice on a virtual range called an engagement skills trainer saving money on live ammunition prior to setting foot on a live-fire range. (U.S. Air Force photo by Senior Airman Shawn Nickel/Released)