I picked up some cases on the range yesterday that I don't know what are. Guess I'm getting dated. They are the same base case as the 223-222. Headstamp was 270 and 73. They appeared to be lacquered steel I suppose Wolf mfg.They were shorter than 223 and longer than 221. probably about the length of a 222, but with a shorter neck. I would give some actual measurements but somehow they got out of me pocket. If I was the mfg I would worry about them causing problems from being put in improper guns with such poor headstamps.