When loading bullets with sabots it is not the bullet that loads hard it's the choice of sabots that load hard. The muzzleloading industry still has no organization to establish standards for bore diameter, rifling land height etc. The Crushed rib sabot is a good choice on a TC which have just about the tightest bore in the industry.
The significant majority of sabots are made by one company, Magnum Muzzleloading Products, regardless of who's name is on the bag or box. They make sabots that are sized for tight bores such as the TC. They also make them for .458 bullets etc. I think they make sabots down to .36 and up to .54 caliber.
http://www.mmpsabots.com/One bullet that gets overlooked more than it should by many shooters is the non-magnum 300 grain Hornady XTP. They are inexpensive and expand well right down to around 900 FPS. They are capable of sub MOA performance out of a TC. You might want to try it with either the crushed rib sabot or a MMP HPH-24.
If you buy your bullets and sabots separately you will usually save 50% or more over buying the same bullet with a sabot that may or may not work with your rifle.
I haven't used Shockey's but switching to Blackhorn 209 might get you a couple of hundred FPS. My Savage is clocking around 1800 FPS with 100 grains by volume of BH 209. I usually use Accurate 5744 smokeless powder though and push them at around 2000 FPS with that.
Lance