But to truly take advantage of the .280, you have to handload. Despite its designation it uses .284-inch (7mm) bullets, which gives you a huge selection to choose from. It can also take heavier bullets than the .270. Factory ammo is loaded with 140-, 150-, and 160-grain bullets, and all will do fine for you. The type of bullet is more important than the weight.
Handloaders can use any of these, but the one that is not factory loaded is the 175-grain. A 175-grain Swift A-Frame, for example, will shoot through two moose and kill a porcupine on the far side.
For a lot of years I’ve hunted with 140-grain Nosler Solid Bases and the old 160-grain Nosler screw-machine Partitions. The former is a quick-expanding slug for deer, the second a much tougher projectile for bigger game. For you handloaders, I’ve had by far the best results with RelodeR 19 and IMR 4831 powders.
If you have a .270 you don’t need a .280. However, independent market research shows that .280 owners are better looking, make more money, get better trophies, and live longer than .270 owners. You read that here first.