Between 1998 and 2002, he was the lead in skip Jeff Stoughton's team during the 1999 Labatt Brier competition for 4 consecutive times.
His team went 10–3 winning in the final against Guy Hemmings of Quebec.
He won a silver medal at the 1999 Ford World Men's Curling Championship.
As a result of his successes, on May 2, 2010, Armstrong was inducted as lead, skipped by Jeff Stoughton with Garry VanDenBerghe at second to the Manitoba Curling Hall of Fame.
[1] He is the son of 1978 Canadian women's champion Iris Armstrong.