Cook began shooting at a 1939 Boy Scout camp and was a member of the McKinley Tech High School Rifle team. He was a member of his High School Cadet Corps, where he was the battalion commander. After graduating from McKinley Tech High, Cook attended the University of Maryland, where he was a rifle team All-American from 1946-1948. He also served as captain of the Air Force Reserve team from 1954-1962. He also remained coach of the McKinley High School rifle team, as well as the basic rifle marksmanship coach for the Navy personnel during World War II from 1943-1963.
Cook's coaching continued with the United States Olympic Committee, where he was the coach for the 1969 and 1993 Deaf Olympic team. He was also the Air Force Assistant Chief Marksmanship Training coach from 1954-1963, and was one of the three sole officers who were in charge of monitoring the USAF Marksmanship Training Program.