IMO you are making a mistake taking a 6mm on an elk hunt. Of course it will kill an elk but that's not the point. It is marginal at best and limits the range considerably. Elk are big critters and can absorb a lot of lead. Elk hunting is hard work and you don't want to be caught under gunned when the opportunity arises. I would suggest the 7 mag as you mentioned or even a 30 caliber of some sort. It does not necessarily have to be a magnum, tons of elk have been killed with the trusty 30-06. Going in under gunned just puts you at a distinct disadvantage. Again, I am not saying you can't kill and elk with the 6 Creedmoor but I think it would be a mistake.