Here in Canada the dates are earlier, I think - like 1885.

Even though it would likely end up in a court case, my 1871/76 Mauser would be exempt from being called a firearm.

It's chambered for the .450 Alaskan. 500gr. at 1,500fps.

Here, and handgun is a handgun if it fires RF or CF ammo and classified by the law pertaining to barrel length, ie; restricted or prohibited. A cap lock or flintlock, if the handgun is verified by the Mounted Police to have been produced prior to 1898, 1885, or 1875 (whichever that day is) is classified as an antique - a non-firearm.

now, I'm going to have to look that up.

The Criminal Code defines an antique firearm as:

Any firearm manufactured before 1898 that was not designed to discharge rim-fire or centre-fire ammunition, and that has not been re-designed to discharge such ammunition, or
Any firearm prescribed to be an antique firearm.

The following firearms are prescribed to be antique firearms under the Regulations Prescribing Antique Firearms:

Black Powder Reproductions:

of flintlock, wheel-lock or matchlock firearms, other than handguns, manufactured after 1897;

(Note that all other reproductions of long guns are considered non-restricted firearms. They don’t need to be registered but a licence to possess them is required. As an example, reproductions of percussion cap muzzle-loading firearms like American Civil War Enfield and Springfield rifles are considered non-restricted firearms and not antiques.)

The b0lded text explains that flintlock, wheel-lock and matchlock replicas are considered antiques - thus no license is required.