Liege black powder 12 mm black powder. FRT antique?

[RichardSukhoi]

Does anyone know how RCMP interprets these? This single shot shotgun black powder was made by Liege in 12 mm based on a model 1871 action. The legislation says antique if "other" than 12,16, 410, etc. So this gun seems to be OK as an antique. BUT, it will accept a 2" 410 shell. It was never marked or intended to accept 410 but it will.

 

[tiriaq]

Check to see if 12mm isn't just the European term for .410.

 

[mkrnel]

In Europe, the .410 bore is commonly referred to as either 36 gauge or 12mm.

• 36 Gauge: This is the most prevalent European designation for the cartridge. It is technically an inaccurate description by the traditional gauge measurement system (a true .410 bore is approximately 67.5 gauge), but the name is well-established in mainland Europe.
• 12mm: In some contexts, particularly in older European usage, it might also be referred to by its approximate bore diameter in millimeters, such as 12mm.