I love my 243ack. It holds a few grains more powder that the standard 243. I set my 17lbs rifle up for 1000yd benchrest and chose the ackley over some of the other 6mm's. My favorite load is a Berger 105gr VLD over H1000 or H4831SC. I do not think you will be disapointed. Remember you can still shoot regular 243 Winchesters through it in a pinch.