Hey Paul, What kinda rifle would you be doing this on? I was just thinking that if you use a single shot, eliminating possible follower and feed problems. That you can blow the taper out .020" and shoulder to 35-40degree, and end up with some gain over a 257 Rob AI, comming close to a 25-06. But it's possible to make a bolt gun operate with such a round also. In all likelyhood, you will have to get the reamers built, no big deal. Dies on the other hand, may bring a premium price. On