I've mostly used lighter calibers on elk: .280, .270 WSM and .264 Win Mag. I just built a .358 Norma for use on elk. It weighs 7.6 pounds scoped, kicks like a frickin mule and lauches 250 grain Partiions at 2850 fps. I've got 3 dates with her this year, one in Idaho and two in Colorado. I know she ain't necessary, but I still like her.
But in reality, my "old reliable" was the .280. I used 175 Mag Tips and 150 grain Partitions in that gun. It was a Ruger 77 that I used for 11 years.