Well I just went down and tried to check myself manually. With the nipple in the gun I put the ramrod down in it and marked it with a piece of tape and marked the tape with a pencil mark. When I pulled it out the pencil mark was slightly past 1/2 a turn. When I measured the tape it was 23 1/2 inches in the barrel. I never knew how to tell if I had a case hardened receiver and looked at mine again. It isn't what I would call a pure bluing, it is more like a swirled look that was mentioned before.