I thought there was a shotgun limit of 3 (non restricted) I've also never seen anymore than 10rds in a centerfire bolt gun......{daydream sequence}....30rd mag in an Enfield would make for a really cool {and expensive} mad minute though!
You may be confusing provincial hunting regs with federal firearms law.
A magazine's limit is measured for the round and platform it is designed for. And hence...
Pistols 'commonly available in Canada' (centerfire and rimfire both): 10 rounds
Semi-automatic centerfire shotguns or rifles (or pistols 'not commonly available in Canada. No, I don't know what that means): 5 rounds
Rimfire rifles (Semi and manually operated): no limit
Manually operated centerfire shotguns or rifles: no limit
"But what about...?"
10 round AR magazines? - The LAR-10 magazines were a new design and the RCMP approved them as being designed specifically for the Rock River Arms LAR pistols. This goes for both the .223 and the 9mm ones
10 round limits for rimfire ARs? - The issue applies to the Chiappa and S&W magazines, and maybe others in the future. These companies sell .22 AR pattern rifles
and pistols with the same magazines. The RCMP argument is that as the magazines are designed for both, the pistol rules apply, and hence 10 rounds. The Spikes and some other patterns of .22 AR mags made by companies without a .22 pistol AR or made by 3rd parties are still okay, apparently. Would the Chiappa mags have been okay if the importer had submitted it for RCMP examination before Chiappa introduced their AR pistol? That depends on how paranoid you are, but it's all hypothetical
Remington 7615 magazines? - Remington's own literature calls it an AR-15 magazine, 5 round limit applies.
9mm rounds in .40 magazines? - technically legal since the magazines are marked for .40 S&W, the fact that they fit and feed over 10 rounds of 9mm is incidental.
The Garand's 8 round enbloc? - exempted by name
Clear as mud? It still is?
There are some specific exemptions:
Lee-Enfields, which by virtue of being manually operated are already exempt, but hey, you're protected twice over!
Garands, as mentioned above
Original drum magazines for a .303 Lewis, .303 Vickers Mark 1, or a Bren gun
Original various 'metallic-strips' for Hotchkiss MGs
Original drum magazines for MG-13, MG-15, MG-17, MG-34, T6-200, etc.
Original belt for a MG that existed pre-1945
Luger 'snail-drum' magazines
Semi-auto pistol mags made before 1910 (The mag, not the pistol)
Integral broomhandle Mauser mag
Webley and Scott Model 12 or Model 15 pistols