Couldn't agree more with Cody, I'm shooting the 150gr eldx at 2800 in my 23" 7-08 and 2850 in the 26" 7-08 with Staball with mag length oal's.
If your building in preparation of an elk hunt, then yes a 7mm rem mag would be great, and fill a void between an 06' and a rum nicely. With that barrel, it will be just as heavy as your rum, maybe more. Do you have a specific weight goal in mind?Well my 30-06 already fills the roll of standard bolt face standard weight rifle. Its 9.5 lbs. My 300 RUM is supposed to be my elk rifle. It weighs 12 lbs now with a 6oz temporary scope. Ill be puting a nx8 on there eventually. I think the 7 mag fits better between those 2 than a 7-08. While perfectly adequate for deer Im starting to gather elk points again so hopefully in a couple years I can that 90% deer hunting down a bit. Thanks for all the thoughtful replies. I haven't changed my mind yet but I have gotten some good questions that have made me think. And kinda reinforced my position a bit.