@Matt Magolan
I've some audacity telling a man whose been on Arctic expeditions what gun to bring. I've never been to the Arctic, but I have used guns in extreme cold weather. Your affinity for the semi-auto is apparent, but have you operated a semi- auto in extreme cold? I too have subconscious mastery of the semi-autos, but I've only been able to mitigate Murphy's Law. I've goose hunted in negative temperatures and witnessed enough semi-auto guns malfunction. Cold constricts metals and alloys constrict differently than steel. In the very cold I can watch my Browning A5 3.5" 12ga bolt slide slowly forwards in attempt to return to battery. No matter how clean, or which lube to no lube would help. The receiver at the least constricts and the bolt is retarded by the shrinking receiver. So get a steel receiver?...Browning BAR Safari 338WM in -20 windchill conditions. I had failure to return to battery.
I've been a Glock owner and user for 20yrs. Untold number of rounds fired through Glocks, instructed others on the use of Glocks, trusted my life to Glock. 100% confidence in Glock based upon 100% reliability in my experience. Until one day...
I blood trailed a wounded TX hog in 90F. heat. I took my Glock 41 45 ACP duty pistol. (The one I had on my hip everyday for my day job) While tracking I bumped into two piglets in the shrubs. I smoked both piglets with one shot a piece. Boom, Boom, squeeeeaaaalllll! Momma took a straight line charge at me. I thought, "OH YES! Mag dump into her head!" Instead is was "OH NO I have a dead trigger". Looked to see my slide locked back and while I was performing immediate action on the Glock, a piglet flopped in the grass and drew the sow's attention off me to her piglet. (She diverted at maybe 4yds from me. I did take note that I could see ultimate concern in her face. I know its strange, but I did. Whale eyed) While she was checking out her piglet I got my Glock back in action and smoked her on her run away. Tell me that doesn't put a pin in your balloon of faith! I would have been better off with a revolver in that instance. F'N Murphy!
A stainless double rifle with composite stock and red fiber optic front sight would be my dangerous game gun. I don't think that exists and the double guns I ever see are 10K plus and French fancy grade walnut. NOPE
A bolt gun is not a fast operating dangerous game gun. CRF style prevents short stroking, but the 4 movements of the bolt is just not the fastest. You also don't want anything with an "eye box". Keep the scopes off the gun.
#1 pick is a pump 12 gauge. At least you have mechanical advantage or influence over the action if it gets sticky in cold weather.
#2 Pick is the 45-70 lever gun. Same mechanical advantage in cold weather.