You don't know if it will work unless you chamber some UNFIRED .280 factory brass. There isn't a vast amount of difference in the Nosler and Ackley chambers, so SOME factory .280 brass will work fine--and some might not.
I emphasize UNFIRED because there can be problems with some fired cases, due to them lacking the slight radius between the neck and shoulder.
John, just to be clear, standard 280 Rem or improved new brass, e.g., Nosler?
