A native of Vancouver, Beaumont joined his hometown Lions in 1960 and, with 53 punt returns for 226 yards, was winner of the Dr. Beattie Martin Trophy for Canadian rookie of the year in the west. This was the first time a BC Lion had won an individual player award. He would go on to play 8 seasons, intercepting 22 passes and becoming the team's second leading punter (both punts and yards,) second only to fellow Leo and all-time CFL leader Lui Passaglia. He also has the longest interception return in CFL history, 120 yards for a touchdown, against the Saskatchewan Roughriders on October 12, 1963.
His best season was 1964, when he intercepted 5 passes, was a Western All-Star, and added a final interception in the Lions first ever Grey Cup victory.
In total he played 123 regular season games for the Lions. He was elected to the BC Lions Wall of Fame in 2003.