The AR-15 and variants is NOT PROHIBITED! It is classified as RESTRICTED and requires you have a restricted endorsement with your PAL. Only restrictions is that you are required to possess an Authorization To Transport (ATT) to take it to/from range, gunsmith, etc... They're available from your Provincial CFO.
Lee-Enfield magazines were also exempted from the 5 round mag limit under C-68/Firearms Act.
It broke my heart having to rivet my genuine Colt 30 round mags for my AR-15 and limit them to 5 rounds. However, you can break high capacity magazines down into their componet parts, and as long as they remain unassembled, are perfectly legal and are classified as unrestricted spare parts! As soon as you put that 20 or 30 rounder together, it becomes a "Prohibited Device" and you're in contravention of the Firearms Act - plus you'll be the cause of the end of Canadian civilization as we know it!
Pain in the A$$ having to load five rounds at a time. I ended up investing just as much in magazines as I paid for my AR. Load them up before heading to the range and then shoot away.
As for Canadian restrictions, compared to the USA, in some ways we have even greater freedoms. For instance, we can still buy and sell long guns by mail, only we now have to complete the transfer process first. No FFL middle man. No waiting periods for purchase of firearms (just bureaucratic inertia) no limit on the number of firearms you can purchase at one time and no Pre-ban/Post-ban restrictions and we can legally buy ARs with shorty barrels under 16". We can also buy guns without every having to leave your house. Give gun shop your information, PAL number, and credit card number, they contact the Canadian Firearms Center who completes the registration transfer and issues TAN and new Reg. certificate, dealer gets okay and ships directly to you, a couple of days and there is a courier knocking on your door with your new handgun, or postman with your long gun. Right now the bottleneck is the CFC. With all the cut backs and lay-offs, transfer times have gone way up and the promised 15 minute transfer time a complete and utter joke.
On the negative side, new shooters and those who sold their prohibited firearms and unintentionally sold their "grandfathered" status are basically $crewed. Can't own any handguns with barrels under 4" and many of the more interesting toys, like AK-47s, FALs, etc... unless a parent/guardian has grandfathered status and leaves firearms to you in their will - there is an exemption for them.
On the up side, we can buy SKS for $100 CDN, Swedes for under $200 CDN and Garands for under $300 CDN, - find the right shop/deal and you can knock another $50-$100 off those prices. We don't have an import ban on foreign military surplus, so we don't have to pay$500-$600US for a Garand.