What sort of rifle is your Creedmoor?
@Formidilosus, who posted just above, can enlighten you a bit on how far one is good for on elk!
I've carried mine on an elk hunt. I didn't get to shoot it at an elk, although Colorado's 4 point minimum rule let one live that would have otherwise died, if he had moved his head from behind a tree. My self imposed limit was 400 yds, which was completely a function of my skills, not of my cartridge and bullet of choice. I've shot 300-500 rounds a year for the last couple years, for perspective.
I would not want to "learn" long range with a magnum.
When it comes to long range hunting, there are certainly people who are qualified to do it, and I'm fortunate enough to know a few. Being from the east myself, the biggest thing that holds me back is not being able to shoot in western wind conditions much. Sitting on the side of a mountain with the wind blasting at you is a bit of a punch in the face sometimes. Many of the days I've elk hunted I'd think long and hard about that 400 yd shot. There is a lot of talk on the net about shooting 500-1000, but it's interesting how that when the camera's are rolling there are a lot of rodeo's........
Best of luck!