In 2012 I went to Alaska. I took a 12 Ga pump shotgun with me. The form was a one page "temporary permit". Filled it out in triplicate as required. Presented it when crossing the border. Was instructed to park and go inside.
I went in and went to the counter, and presented the form. An agent walked outside with me to inspect the gun. I had it secured in a locking gun rack under the bed, unloaded. I pointed to where it was at, and handed the agent the key to the lock. He instructed that I go wait outside, which I did.
He came out a few minutes later and walked past me, only stating "nice lock". I went back inside and paid my $25 permit fee, they stamped the form and I was done. From then on at every border crossing I came to I presented the permit and the agent waived me through without question.
The only warning is that on the permit form you fill out, under the reason for the gun write "wild animal protection" and not personal protection. You are not allowed to possess a firearm for personal protection in Canada. I also didn't bring any shells for the gun, opting to purchase them while in Canada, which was easy.
There were other parts to the overall border crossing story, but that was the only part that pertained to the firearm. I had also opted to leave a hunting knife at home as I didn't want it to become an issue. I later learned that does not regulate knifes so it would not have been an issue at the border.
