Re: 7mm or .30
+1 on what AJ stated.
Foe elk, the bigger the better. I also look at bbl life as a concideration. 300 RUM life is short and glorious yet is longer than the 7mmRUM.
I am moving from the 300 RUM to the 300 WSM. I will still use a long action so I can seat those heavy bullets out far to maximize case capacity. I will loose some velocity but gain much more life and ease of tuning. The 300 and 7mm RUM's are a bit tempermental. A bit too much so for my taste.
IMHO, the 338 RUM or EDGE with 300 SMK's would be the ultimate 1000 yard+ elk harvesting machine.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.