Ain't that the truth! The Snider was used by the Canadians so it is a historical arm on this continent, and it is likely that in the old days some 'wandered' back and forth around that western border area. Of course, since the first ones were muzzle loader conversions of the 577 musket the projectile had the same effect. It wasnt until later that the 'smallbore' ballistic advantage of the 45cal. came into prominence.
The 577 Snider was chambered in sporting arms and likely wherever the British were stationed as ammo was readily available. The number, size and type of game taken around the world can only be imagined.
BTW, my brass cases can hold a carbine BP load of 50gr. on up to around 85gr.; I do not want to ever pull the trigger on an 85gr. load in mine, though some guys do!