Soldiers fire three M116 pack howitzers during a change of command rehearsal for the Army Reserve’s 108th Training Command at Fort Jackson, S.C., Sept. 19, 2015. The soldiers are assigned to Troops Battalion Salute Battery, 171st Brigade. The M116's are called “pack” howitzers because they were originally pulled by pack animals. U.S. Army photo by Sgt. Ken Scar