U.S. Army soldiers light up the range with tracer rounds. U.S. Army soldiers assigned to 3rd Battalion, 157th Field Artillery, Colorado Army National Guard, light up the range with tracer rounds as they fire the M-240B medium machine gun with the help of night optics at Fort Hood, Texas, on April 25, 2009. The battalion, which arrived at its mobilization station on April 18, is deploying this summer in support of Operation Iraqi Freedom. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 451452-Q-EMP91-436.jpg Photo Gallery