I personally have never owned or shot a 7mmRUM so I cant compare the two. I have however hunted with a 300RUM for a couple years and really like it. I also do not hand load yet, just cant seem to find the time at the moment. If you do decide to go with the 300RUM dont bother shooting any factory load under 180gr. I tried some Remington 150gr and it wouldn't group worth a crap. After that I tried Remington 180gr Scirocco and the groups got much tighter. The HSM Trophy Gold also does well, I tried the 185grVLD and really liked it so thats what I been sticking with. Hope this helps with your decision.gun)
I have both on a 700 action and anticipate a short barrel life in one and even shorter life in the other. They both have a practical purpose and shooting them often other than for hunting is not one of them. If you're set on the 7 or 300 RUM definitely my first choice would be the 300. 7RUM can also be a bearcat to reload for. Also consider the 338 Edge using the wildcat 300 RUM case as a parent if a RUM is a must. Many positives are said about that load.