I would go with the 300g Shockwaves and a 100yd max range unless you get more range time. Use 75yds as a min for sighting in. With more time you can get the 200g Shockwaves to shoot great but I have seen them keyhole targets when underpowered or with too long a twist. I just plain do not trust Powerbelts with all the bad press they have had but they sure shoot good in some rifles.

Good luck happy hunting.