Thanks guys. I really only want to change out the barrel, true the action, and the standard stock modifications. So, the 264 Win Mag option sounds more reasonable with what I want to do. I'll have to do a little more research on it. The end goal is to have decent long range rig that doesn't pound the snot out of me every time I shoot it. Don't get me wrong, I like my 300RUM, but it's not very pleasant to shoot off a bench.

6.5wsm would work also......... a little mag work but doable.
woofer

It is possible to bush the bolt face and change the extractor to end up with a 284 sized bolt. Would probably cost an extra 50 bucks or so.
If you want to stay with the magnum bolt face and approximate the 6.5/284,you could always go with the ^.5 Rem Mag. Capacity is a bit greater than the 284 but still within reason. Regards, Bill.