The Canadian Government purchased primarily 5" barreled Military and Police Smith & Wesson 38 S&W revolvers during WW2, there were small batches of 6" barreled revolvers also purchased. The issue of 5" barrel model 10 Smith & Wesson revolvers is a carry over form the wartime purchases. I have had both 5" and 6" Military and Police model Smith & Wesson revolvers in my collection...the Military and Police revolver became the Model 10, based on the K frame revolver.
The Canadian military also purchased a very small quantity of the New Century (Triple Lock) and large number of the MkII (Second Model Hand Ejector) revolver during WW1, both were N frame revolvers chambered in 455.