Elk are way harder to kill than moose.I've shot truckloads with the 6.5x55,.270,30-30 and a few with a .338 win mag.No difference in how quick they died.A friend of my son's has a spinal injury so larger calibers are not an option.His moose dropped with a .243 Use premium bullets ,Partitions,Barnes TTSX etc. They aren't cape buffalo.A high shoulder shot and they go nowhere,but keep in mind they have 6" on hair on the hump so allow for that.