Born to a wealthy family, Karl-Robert Ameln started sailing at a young age, as his father Robert Ameln was the owner of the ship building company Jungnerholmarna and Oskarshamn shipyards. As a member of the Royal Swedish Yacht Club, Ameln competed at two Olympics, winning a bronze medal in the 1948 6 metre class and placing fourth in the same class in 1952. Educated as an engineer at the KTH Royal Institute of Technology, Ameln worked his entire career with the family businesses, serving as director of Oskarshamn shipyards from 1959-64 and director of Jungnerholmarna from 1959 until his retirement in 1981.