I'll hazard a guess that way back when England's gun laws started to become draconian in nature, a fair number of rifles were 'evacuated' back to this side of the Atlantic- Canada being a logical destination. Any gun imported into the UK had to be proofed at the gov't proof house before it could be sold, as well as any gun freshly built there.
Many years ago I had a Model 1893 Marlin B grade (barrel marked "for Black Powder") with a full set of English proofs. Bought it through the mail from someone in Minnesota. (Kind of close to Canada, no?)
A gun is a tool, Marian, no better or no worse than the man who uses it...
