The Canada Border Services page on this states: "Canada's firearms laws help make Canada safer for residents and visitors. When you enter Canada, you must declare all firearms and weapons to the Canada Border Services Agency (CBSA). If you do not, they may be seized and you could face criminal charges. You need documents to prove that you are entitled to possess a firearm in Canada, and you must transport it safely."
Options? Consider leaving these kind of weapons at home or store them with a storage service somewhere near the border before attempting to cross into Canada.
- While we cannot recommend specific companies, please comment below if you have had personal experience with gun storage companies in our area >> https://www.yellowpages.com/sweet-grass-mt/self-storage that may be useful to your fellow travellers.