Congratulations of the new Kodiak rifle. Being a CVA it will probably shoot powerbelts real well. 80 - 100 grains of powder is all you will need. If you push powerbelts too hard it seems the accuracy falls off. I would suggest some of the 295 and 348 powebelts for starters, but it really is hard to say what the rifle will like. All you can do is try different loads and charges.