Belts are not magazines
Yes they are, according to the criminal code. I can even quote it for you.
That very, very clearly states the belts as a type of cartridge magazine. End of discussion. I can literally not make it any clearer than that.(2) Paragraph (1)(a) does not include any cartridge magazine that
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(f) is of the “belt” type consisting of a fabric or metal belt, is not a reproduction and was originally designed or manufactured for the purpose of feeding cartridges into a automatic firearm of a type that was in existence before 1945.
Read it here if you don't trust my copy and paste skills:
http://laws.justice.gc.ca/en/ShowFullDoc/cr/SOR-98-462//20090805/en