The bullets seem to work at 270 AI velosities as well. I used the ole 270 on 29 sheep hunts, and 50 yrs of deer and elk hunts so their is no argument that the 270 is more than sufficient. I shoot an AI now only because I want to, not because of any short commings in the parent cart. There is a gain in vel that is more than Ackley indicated probably due to superior components and measuring devices. With that said build yourself one if you want one or shoot what you have if that is your pleasure, I doubt that any game animal (shot correctly) gives a damn. jm
