The brown Sabot is for 45 Caliber and the Blue is 50 Caliber. When I had Mountain Molds make me the Mould I had the 1-28 twist in mind and I've shot them in both 45 & 50 Caliber muzzleloaders equally well out to 175 yards. Mountain Molds no longer offers to make smooth sided Moulds but I've noticed that Accurate Molds has some listed that are very similar for anyone interested in casting. I've seen those cheap shots your talking about and believe they have a lot of potential.
This Optima is the pickest rifle I’ve ever fired it wouldn’t group 180’s or 195’s but boy did it love PR bullets 200 gr Deadcenter over 90 grains of bh209 . I wish I’d have a chronograph I’m guessing close to 2000 judging by the cup on the mmp sabot.
I have two .45 caliber muzzys. One is a T/C Hawken stock and hardware with a GM LRH 1:30 twist and the other is a T/C Encore Pro Hunter. The Encore I haven't shot yet and plan to when I get back up north in May. The target below was fired at 50 yards with open sights from the GM barrel using 80 gr of Goex FFFg and a home cast 340 gr paper patched bullet. The bullets in the second pic are my cast 390 gr and will also be paper patched and tried in both rifles. I hope they shoot as good as they look.