Carl Eiríksson competed in both pistol and rifle sport shooting events, but it was in the latter that he specialized. He only competed in one edition of the Olympics, in 1992, but at the age of 62 years, 213 days he was the oldest competitor at the Games, and remains the oldest ever representative of Iceland by nearly two decades as of 2016. In Barcelona, he took part in the small-bore rifle, prone, 50 metres event and placed joint-50th with Norbert Sturny of Switzerland. Domestically, he won numerous championships into the 1990s, until his retirement from active competition in 1997. By career, he was an engineer.