The 22 CM is essentially is 22-250ai with a 30* shoulder. I use 25 CM brass sized in a 250AI die in my 250AI. Perhaps Hornady marketing reinventing the wheel?I'm using RE23 In my 22-250 AI running 80 Amax bullets. I have some 80.5 Full bores I'll try next. 500 yard groups around 2" but the day I shot the group, it was very hot and lots of mirage. Couldn't get a good clear focus of the bull. Hoping for a cooler day with better conditions for an accuracy test. Barrel is a 30" MTU 8 twist. Velocities were around 3550. My next barrel may be the Creedmoor depending on brass availability. Good looking group on steel. Post some pics of the rifle.