Not 100% sure, but I seem to recall a requirement for some sort of permit to allow possession of the rifle on Canadian territory, which must be in hand prior to the trip.

But I'm not a hunter, just a fan of responsible civilian firearms ownership.

Frommer's site on Canadian entry & exit requirements (http://www.frommers.com/destinations...216020032.html) had this to say:
"As for firearms, visitors can bring rifles into Canada during hunting season and for the purposes of hunting. Handguns and automatic rifles are generally not allowed. Fishing tackle poses no problems, but the bearer must possess a nonresident license for the province or territory where he or she plans to use it. For more details concerning customs regulations, contact the Canada Border Service Agency (tel. 800/461-9999 within Canada, or 204/983-3500; www.cbsa-asfc.gc.ca)."

Looks like that is about 4 years old.

From the US State Department at http://travel.state.gov/travel/cis_p.../cis_1082.html :
"IMPORTATION OF FIREARMS: Firearms are strictly controlled. As of January 1, 2001, visitors bringing firearms into Canada, or planning to borrow and use firearms while in Canada are required to declare the firearms in writing using a Non-Resident Firearm Declaration form. Multiple firearms can be declared on the same form. At the border, three copies of the unsigned declaration must be presented to a Canadian customs officer. The declaration will serve as a temporary license and registration certificate for up to 60 days. The Non-Resident Firearm Declaration costs $50 (Canadian). Visitors planning to borrow a firearm in Canada must obtain in advance a Temporary Firearms Borrowing License, which costs $30 (Canadian). The form must be signed before a Canadian customs officer and the fee paid at the border. In order to save time at the border, Canadian authorities recommend that visitors complete the declaration form, but that they not sign it, and make two copies of the completed form before arriving at the port-of-entry. Requests made at the border for photocopies of the form may be denied. Full details on this new policy are available at the Canadian Firearms Centre website, http://www.cfc-ccaf.gc.ca, under the heading "Visitors to Canada." The Non-Resident Firearm Declaration and the Temporary Firearms Borrowing License applications may also be obtained from this website.

Canada has three classes of firearms: non-restricted, restricted, and prohibited. Non-restricted firearms include most ordinary hunting rifles and shotguns. These may be brought temporarily into Canada for sporting or hunting use during hunting season, use in competitions, in-transit movement through Canada, or personal protection against wildlife in remote areas of Canada. Anyone wishing to bring hunting rifles into Canada must be at least 18 years old, and the firearm must be properly stored for transport. Restricted firearms are primarily handguns; however, pepper spray and mace are also included in this category. A restricted firearm may be brought into Canada, but an Authorization to Transport permit must be obtained in advance from a Provincial or Territorial Chief Firearms Officer. Prohibited firearms include fully automatic, converted automatics, and assault-type weapons. Prohibited firearms are not allowed into Canada.

In advance of any travel, please contact a Canadian embassy or consulate, or the Canadian Firearms Centre (http://www.cfc-ccaf.gc.ca) for detailed information and instructions on temporarily importing firearms. In all cases, travelers must declare to Canadian Customs authorities any firearms and weapons in their possession when entering Canada. If a traveler is denied permission to bring in the firearm, there are often facilities near border crossings where firearms may be stored, pending the traveler's return to the United States. Canadian law requires that officials confiscate firearms and weapons from those crossing the border that deny having them in their possession. Confiscated firearms and weapons are never returned.

Please see our information on customs regulations. "

Hope that helps.