Re: 280 ackley
162 Amax, 168 & 180 Bergers of all flavors, 168 and 175 SMK's will all work very well in this chambering.
Ballistically it is a very close twin to the 7mm Rem SAUM.
For those heavy bullets H4831sc and RL22 work in the 160-170 range, H1000 works really well in the 170-180 range.