I have been using the 280 for 10 years. I have a Remington 700 that I rebarreled and chambered for the 280. I reload for the cartridge and it is wonderfully accurate. I do not believe the 280 Ackley to be more inherently accurate. If you choose a quality rifle and spend some time looking for that magic load, I believe you will have a tack driver. I shoot as much as I can. As for a gain of velocity you will gain 100-150 fps over the standard 280 going with the Ackley. This is not substantial and in my opinion not worth doing. However, after several thousand rounds through my 280 the throat was eroded and I had my rifle rechambered for the Ackley. It' s not more accurate than it was before. I can reach almost 3000 fps with a few different powders and a 175 gr Partition. The 280 Ackley is only slightly out paced by the 7mm Remington Magnum. I could get around 2860 with the same 175 gr Partition when loaded in the standard 280. As with the standard 280 and the Ackley version most of the published reloading data is anemic. Looking for pressure signs and velocity over my chrony I have in nearly all cases been able to go 1.5-2.5 grains over the listed maximum in my manuals. These are just the experiences I have had.

I guess to give a final answer I would purchase a factory rifle in 280 with a 24" barrel. If you shoot alot and burn out the barrel then rechamber to the Ackley. Otherwise, I would just buy a standard 280. I use 140 gr BT on whitetail deer and 175 gr Partition on elk. Remember that shot placement is the key.