and with the barrel slices sharpened they give four faces to scrape with before needing to be touched up on a stone. Use one edge and then turn the barrel slice 180 degrees for the other edge on the same face to be used then it can be turned for the other end and its two edges but there are quite a few barrel channels that get done with the 4 edges. The bends in bolt shaft are the same. It is just how they lay on the bench that makes them look different.