I must be seeing this rifling wrong - it appears to me to be almost the exact opposite of Henry rifling in that the wide groove, normally flat botomed, is raised in the centre witht he grooves themselves being only the corners. This is evident by the corners being the largest diameter, it: the grooves. The higher crwon shows this. It is Henry-type, sort of, with reversed main groove becoming a land.

In an angled crown such as on this beautiful rifle, the tightest part of the bore, the lands, provides the longest bevel in the crown.

Of course, this might mean nothing in the shooting prowess of the gun. It is a most interesting design indeed.