Re: berger seating depth?
I start with VLD's for fire forming brass at .010" in the lands. Then start moving out .005" at a time to .010" off the lands. Look for a sweet spot in the groups at 300 to 500 yards and the lowest ES. The last rifle we worked up was a 300 win with 210's. They liked .005" in the lands. All are different and you need to find what your rifle likes.
In my Weatherby's with freebore I just load them .020" short of the mag box length. Although I have no first hand experience with RUM's, I would think since they too have the freebore it would work for them like the Wby mags.