RE: 300 RUM for Alaska??
I would use the 200gr. Nosler Partition for the 300 RUM, and a 160gr. Nosler Partition, Fail Safe or a 150gr. Trophy Bonded Bear Claw. You might want to get into handloading you will have a wider choice of bullets.
I own a 340 Wby. Mag., and I love it's preformance. One day I would like to use it for brown bear. Good luck