+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.