I've been searching for information on the 223 Rrem Ackley Improved and coming up next to dry. Can anyone shed some light on this cartridge? I have read through some information on the Ackley Improved cartridges and understand that some cartridges show a measureable improvement, while others are marginal. Does the 223 Rem fall into the "improved" or "marginal" category? My research has revealed standard dies being available from the "mass" producers and the barrel manufacturers offer the chambering. as in another post of mine, I'm planning on building a varmint rifle for ranging out to 300yards and would like to stick with a low-recoil 22cal cartridge. Before what I've read, the standard 223 Rem is reaching the end of its effective range around 250-300yards. I am usually competing against some light to moderate winds where I'll be hunting. With this in mind, I'm wondering if the 223 Rem AI with heavier,higher BC) bullets will meet my range requirements. Thanks for your feedback.