Speaking of Harvester sabots, your safest bet would be to try the black crush ribs sabots. But as you should know, every muzzleloader, even in a model/brand, is different. The black smooth could shoot better in your gun. Or the black long (300gr and larger) could be the ticket. Or maybe MMP sabots work best in your ML. There is no way around trying the different sabots available to get the best combo.