Aside from the 1948 Olympic Team, Cook also was a member of the U.S. teams at the 1949 International Shooting Union World Championships, the 1951 Pan American Games, the 1952 ISU World Championships, and the 1954 ISU World Championships. He won two medals at the 1949 World Championships and one medal in 1952. In 1953 and 1957 he won the National Gallery Rifle Championship.