 In April 1952, after running afoul of a superior, Kilmer chose to volunteer to serve as a corpsman with a Fleet Marine Force (FMF) unit.After completing instruction for combat field training in June at the Field Medical Service School at Camp Pendleton, California, he was assigned to the 3rd Battalion, 7th Marine Regiment, 1st Marine Division.In Korea, Kilmer was a member of H Company, 3rd Battalion, 7 Marines.