is there any characteristics i should be looking for in a 6.5 or 6.8 barrel, for instance rate of twist etc, if im looking for something that will shoot heavier bullets accurately? Any recommended makers to look for or stay away from?

i hate to have a rifle sitting basically unused, maybe one day i can get into 3gun with it, but until then its basically my shtf gun. If its going to cost more for the upper than a decent hunting rifle ill just leave it be. Was hoping to simplify my gun life a bit and let go of 2 deer rifles in favor of this.