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.