Coll enlisted in the Marine Corps a month after graduating from Northeast Catholic High School in 1956. He was a non-commissioned officer for his first several years in the Marines, but took officer training and in July 1967 was sent to Vietnam, where he became a platoon leader in Company D of the 1st Reconnaissance Battalion, 1st Marine Division. He was promoted to captain two months before dying in Quang Tri Province on Sept. 13, 1967. He was 29. Survivors include his wife, parents, a brother and a sister.