If you want to stick with Powerbelts, I'd use either the 275 grain hollowpoint or 300 grain Platinum with 2 pellets (if you want to stick with pellets). I'd highly recommend switching to loose powder if you want to get the best performance and accuracy out of your Kodiak. With loose powder, I would use 70 - 80 grains with either Powerbelt I mentioned.

For the ranges you are describing, another good option would be the 200 grain Hornady XTP with 2 pellets or 80 - 90 grains of powder.

I get the best accuracy with the 200 grain SST and 90 - 100 grains of powder, but at the ranges you will be hunting, this type of load is not really necessary.