Yes .... at least under SASS (Single Action Shooting Society) rules, which are followed for the most part by clubs in Canada. The specific provision in the SASS Shooter's handbook reads, in part -
"Rifles or carbines used in the main and team matches must be original or replicas of lever or slide action rifles manufactured during the period from approximately 1860 until 1899, incorporating a tubular magazine and exposed hammer. Rifles with box magazines may not be used."
The 2009 SASS Shooter's Handbook is available in PDF format in its entirety, for review or download, here -
http://www.sassnet.com/Downloads/RO/SASSHandbook(15).pdf
The other main organization for this type of shooting is the National Congress of Old West Shootists, although generally speaking its unique rules, to the extent that they differ from those of SASS, are much less likely to be encountered in Canada. NCOWS is rather more historically oriented, As a result, it disallows some firearms which are approved under SASS rules, but by the same token allows many firearms which are disallowed by SASS. One very notable difference is that NCOWS allows double-action revolvers and even very early semi-automatic handguns, provided they are designs which existed by 1899! The NCOWS Bylaws, which incorporate their rules, can be viewed here: http://www.ncows.org/Bylaws.htm
