Most of the later model CVA's show a preference for the Harvester EZ load smooths regardless of your bullet choice (proper diameter requires of course) but also shoot most 458 diameter bullets equally well in an MMP orange 458x50 sabot. The powder charge sweet spot usually comes in with 110gr BH209. That isn't to say that you can't use less & get good groups. It's just a consistent thing with BH & CVA's

I shoot a Lehigh 458/300 CF subsonic, 110gr Bh209, orange MMP sabots, Fed 209A primers out of my Accura MR with great accuracy.

Hope this helps, Greg