The 280 Remington Ackley Improved (280 AI) is an "improved" or blown-out verions of the 280 Remington, meaning the chamber is enlarged so that cane body taper is remove, increasing powder capacity and thus increasing velocity. Just one of dozens of wildcat cartridges developed by Parker O. Acklely during his long career, it has progressed into factory chamberings. With its staight case and sharper shoulder the unbelted 280 AI is capable of velocity very close to the 7mm Remington Magnum, but retains the smaller case (and thus magazine capacity) of the 280 Remington. Like most "improved" cartridges it is safe to fire 280 Remington cartridges in a 280 AI chamber; there is some loss of velocity due to case expansion, but this is the normal process by which 280 AI cases are fire-formed for reloading.
