RDD, I don't, of course, know for sure. However, it seems logical to me that the suppliers of barrels would have also supplied ribs. It seems like they would have experimented with a variety of square patterns and offered the most attractive to their customers. Is the untwisted short rib part of a barrel joining system? Or, is it just a rib? I've seen short ribs such as this frequently, but not the contrast in material. I'd guess on a gun of that quality that nothing was by chance or for cheap. I'd bet they did it that way because they thought it looked good. IMO, they would have been right, too!!
