I've shot most stuff up here with my Whelen, almost exclusively using 250gr bullets, and have never found it wanting. I also don't shoot factory ammo and aside from one old box of federal I saw covered in dust on a shelf in Kodiak years ago the Remington stuff is about the only factory I've seen. I also haven't been impressed with the Montana rifles I've handled and worked on regardless of calibers. I would much rather get a Ruger and sink some money into customizing it to my liking. In fact my Whelen is a M77 I rebarreled and tweaked.
Get yourself a used press and some basic reloading stuff at a garage sale or gunshow and forget the factory stuff. You'll shoot more, shoot better ammo, and won't have to worry about availability. Before you fly into the bush scatter a few extra rounds into each pack, camp box, or drybag you're taking that way if you forget or loose your ammo you'll at least have two or three. There's no TSA at the floatplane dock so you won't have to worry about that.
