Yes, seat No Excuses right on the powder charge. I only shoot 85 grains because if you go more the recoil can get a little brutal.

As for the Harvester Sabots in a T/C barrel, get some of the T/C Mag Express sabots and try them. For the .430 diameter I think the green .429-.430 should work just fine. Keep the charge around 100 grains.

I will not swear to this and Triple Se7en is much more up on sabots, but T/C used to be made by MMP I think. I used to have trouble loading Harvester sabots myself.... In fact I broke a short starter trying to get one down the barrel...