Well congratulations on your new rifle. I can understand your thinking about wanting to be able to reload for your new rifle. The big problem is you don’t know what any load will do until you shoot it in YOUR rifle. I would have it regulated with the Norma ammo. You can always duplicate that load if you have a chronograph. You can’t do a good job of reloading for a double if you don’t have one. When you get your rifle shoot some of the same ammo it was regulated for and record the velocity (I would try to get some from the same lot) H&H should be able to tell you what lot of ammo was used. I would also try to by a small supply of this ammo. This way if you have any problems with your reloads you will have enough ammo to shoot. You didn’t share how long you ordered the barrels on your new rifle that can have a Bering on how fast it will shoot a given load. Next don’t get to hung up on a fixed velocity any 570 gr bullet at 2000+ fps will do the job.
Good luck
Bill