Cpl. Calvin V. Montgomery uses his whole body to pull the lanyard of an M777 Howitzer, firing a 155 mm round March 11 during Dragon Fire Exercise 15-2 at Pohakuloa Training Area, Hawaii. Howitzers are used by artillery batteries to provide suppressing fire for ground units. Montgomery, an Eatonton, Georgia, native, is a radio operator with Headquarters Battery, 12th Marine Regiment, 3rd Marine Division, III Marine Expeditionary Force. - Cpl. Calvin V. Montgomery uses his whole body to pull the lanyard of an M777 Howitzer, firing a 155 mm round March 11 during Dragon Fire Exercise 15-2 at Pohakuloa Training Area, Hawaii. Howitzers are used by artillery batteries to provide suppressing fire for ground units. Montgomery, an Eatonton, Georgia, native, is a radio operator with Headquarters Battery, 12th Marine Regiment, 3rd Marine Division, III Marine Expeditionary Force.