Whal, I can't quote the specific section of the law but it all hinges on the ignition method.
Last fall I applied to register my cannon since all pistols and rifles have to be registered up here and since my ATF Form 6 has a space for the Canadian registration number. (The Form 6 is required when I travel to the U.S. with firearms.)
The folks at the Canadian Firearms Centre didn't want to register my cannon - they said if I can use a fuse, it doesn't fall under the firearms law. I told them I can also use cap ignition and they said it still doesn't matter because it's a BP muzzle loader. I told 'em I STILL want it registered. They said they would. It will be 1 year on November 5 and I STILL don't have the registration!
The chance of the RCMP giving you any grief is next to none! The only question would be the mood of the border guard when you hit Canada Customs. If he (she) is in a grumpy mood, they might ask ya a whole lot of questions but there's nothing in the law to stop you from bringing it thru Canada.