Corporal Piercy was a member of the Reconnaissance Company, Headquarters Battalion, 1st Marine Division. He was listed as Missing in Action while on a night reconnaissance when ambushed at "Grey Rock Ridge" just east of the Panmunjon Corridor near combat outpost "Nan" in South Korea on 12 April 1953. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

Piercy was awarded the Purple Heart, the Combat Action Ribbon, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.