I have a 30 Nosler on a Stiller Predator with a Proof barrel and SHV scope on it all sitting in a McMillan bedded stock. I've been trying 215 Hybrids, 212 ELD-X, and 200 ELD-X with Retumbo and H1000. Best groups are around .75 and maybe .5 at best a couple times. About 50 rounds shot through it so far, broke in correctly and my reloading techniques are very detailed best that I know of. I also make sure that only 3 shot groups are taken and let it completely cool down after each group is shot in the shade. Any good advice or experience with this similar issue or caliber is appreciated.