280ai die with a .294 bushing in it, or a bushing in that range anyways depending on how much neck tension you want.I haven't found anyone who makes 6.5x280 ackley dies or a seater die. I figured I could use a 280 ackley die with a smaller bushing but I can't figure out the seater. Trying to decide between a 6.5x280 ackley and a 6.5saum on a long action.