Jon, the 1:120 twist rifle submitted by Baker won the competition. Part of the selection criteria besides the smallest group for 12 shots was the propensity or lack of it to foul, again Baker's rifle proved to be much less prone to this than the others.
The original gun tested was bored to take 12 balls/# where the production models that were fielded were bored to take 20 balls/# with the other design features essentially the same.
Dan, Baker for the most part used rifling with 7 square lands and grooves or equal width with a dept of .015. However, on the Carbine models the standard seems to have been 7 angular grooves with the width either equal to the grooves. However, Ketland in 1790 used 7 lands 1/2 the width of the angular grooves.
Of further note the 1776 Pattern Rifle had a 1:27" twist with 7 square cut lands and grooves of equal width. The Ferguson rifle had a 1:56" twist with 8 lands and angular grooves with the that slightly narrower than the lands.
I tend to believe that the proper twist for any rifle is that twist that works the best. All of my rifles have 1:66" twist and they shoot far better than I so I'm happy. But then I'm a creature of habit. I also believe that the black powder shooter when shooting off-hand induces far more errors than any of the technical variations of the weapon being shot.