[1] In his twenties he took up riding in point-to-points, with his first win coming in 1923 on Dean Swift, a horse he owned.
[2]: 24 In the following years, Dreaper cemented his reputation as Ireland's leading trainer with horses such as Storm Head, Hasty Bits, Shagreen and Fortria.
The only major race that he never won was the Grand National, coming second in 1970 with Vulture and in 1971 with Black Secret, ridden by his son Jim.
The Irish Grand National winners were Prince Regent (1942), Shagreen (1949), Royal Approach (1954), Olympia (1960), Fortria (1961), Kerforo (1962), Last Link (1963), Arkle (1964), Splash (1965) and Flyingbolt (1966).
[2]: 24 Dreaper married Betty Russell in St Patrick's Cathedral, Dublin, in 1945, and had a son and two daughters.