By the way, zibzer, if you didn't gather it from my post, the most common Canadian-issue handgun during the Great War was the .455 Smith & Wesson Hand Ejector revolver.
A fact not well-known is that, from Confederation, Canada has never adopted
any British pistol design as its primary-issue military handgun (... with one "small" exception ...)
Our primary-issue military handgun acquisitions - (invariably when it was "necessary" get something) -
- 1855/6 -.36 Colt Model 1851 percussion revolvers (albeit produced in Colt's London factory)
(The "necessity" arose when the United Province of Upper & Lower Canada was required to undertake more responsibility for its own defence, including arming its Militia, which it began to do under an new Militia Act passed in 1855. This situation arose after Britain was forced to withdraw most of its troops from the self-governing colonies to meet the massive demands of the Crimean War.)
- 1885 - .45 Colt Model 1878 Double Action revolver
(The "necessity" - the 1885 North-West Rebellion.)
- 1900 - .45 and .455 and Colt New Service revolver
(The "necessity" - the Boer War, the first time Canada sent any troops "overseas".)
- 1914 - .45ACP Colt Government Model pistol
- 1915/16 - .455 S&W 2nd Model Hand Ejector revolver
(The "necessity" should be self-evident, from the dates.)
- 1939-44 - .38 Smith & Wesson Military & Police revolver
- 1944 to present - 9mm Browning High Power pistol (all manufactured in Canada by Inglis in 1944 and 1945)
(Again, the "necessity" should be self-evident. Other than having since acquired a relatively small number of Sig-Sauer pistols for issue in limited circumstances, the "necessity" to replace the Inglis has apparently not yet arisen in its 70-plus year service history!

)
The "small exception" mentioned above is the .38 Enfield No. 2 Mark I revolver, adopted between the wars by the fledgling RCAF, which acquired 235 of them in 1935, and another 350 in 1937. By the end of WWII a total of about 3,500 Enfield revolvers had been acquired (all destined for the RCAF, as far as I am aware) but the Air Force also got many .38 S&W revolvers, of which Canada acquired a LOT more -well over 118,000 of them according to Clive Law's "Canadian Military Handguns 1855 - 1985" ...
(I am very fortunate to have an example of each of these Canadian-issue handguns in my collection...)