Dugald McInnes lived the first half of his life in his native Scotland, where he took up sport shooting and was a member of the 1st Volunteer Battalion Highland Light Infantry. He moved to Manitoba, Canada in 1904, joining the 90th Winnipeg Rifles, before settling in Edmonton, Alberta in 1907 and becoming a part of the 19th Alberta Dragoons. At Britain’s prestigious Bisley tournament, he competed for Scotland through 1905, and for Canada thereafter. During his final year with Scotland he won the Alexandra prize by having the best score with seven shots at 200 and 600 yards. With Canada he won the Kolapore (teams of eight with seven shots at 300, 500, and 600 yards) and MacKinnon (teams of eight with ten shots at 800, 900, and 1000 yards) Cups several times, also, on occasion, earning the Freemantle Cup as top scorer in these events. Perhaps his most notable success, however, came at the 1908 Summer Olympics where, alongside Charles Crowe, William Eastcott, Harry Kerr, William Smith, and Bruce Williams, he won a bronze medal in the military rifle team event. He was also joint-16th, alongside Thomas Fremantle of Great Britain and Charles Winder of the United States, in the 1000 yard free rifle. During World War I he served overseas with the 9th, and later the 26th Battalion, of the Royal Canadian Army Service Corps.