I tried 5744 powder to provide "slow" 400 grain lead bullet loads. It is a great powder for Black Powder velocities in single shot rifles, but it does not burn clean. I abandoned it right away as it tied up the action in just a few shots. This powder is known for lots of unburned powder. Even in 45LC loads it would tie up a cylinder. Unburned kernels would be left in the chamber and when a new round chambered, it would jam the action up tight. My recommendation is to avoid it.
The Savage Muzzle loader uses twice the powder volume (from what I have read) of this powder in comparison to what you can get into the 45B case.
IMHO you have three readily available commercial choices for powder, listed in my order of preference -- Lil'Gun, W296 and H110.
"They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety. " - Benjamin Franklin." Member #55 of the 450b forum.
Whow -- nice to see powder manufactures are steping up to the plate. Am very interested in your results. This post should be put into our reloading section on the excel sheet.
If that powder is in the efficiency sweet spot across the entire weight range of bullets they list, that would be pretty impressive. With the powders I've been using, one is more efficient at the lower end, one is more efficient in the middle and one is more efficient at the upper end, all else being equal. Do keep us in the loop on your experiments.
Hoot
In Theory, there is no difference between theory and practice. In Practice, there is.