I use the Cutting edge C21 180 grain bullet with 97.5 grains of retumbo. I get a bc of right at .6 with it at 3470 fps out of my 1-10 twist 28" barrel. Run the ballistics and you see why I use it. It performs very well on game.
I shoot a 30-378wby and one of my buddies shoots a 300UM rebarelled with a 28" tube, our Velocities avg within 25fps....here is a link to a post I just did sowing some field results I shot recently with 230gr Bergers and 180 & 200 Barnes TTSX.....hope it helps you decide.