Hey, T-Square, good to hear from you.
Like T-Square, I have owned a lot more .270's than either 7mm Mag or .280. In my experience .270's are easy to get to shoot, and they do the same things to game as the two 7mm's, so I tend to stick with them.
Have owned two .280's and loaded for a few others. The two I owned were a custom job from Dave Gentry, which was of course very accurate, and an out-of-the-box Winchester Model 70 Feeatherweight Classic that was just as accurate!
The last 7mm Remington Magnum I bought was a very slightly used Remington 700 ADL synthetic. The first three groups averaged well under .6". Over the years my other 7mm mags haven't been quite that accurate but then I didn't know as much about handloading back then.
Like T-Square, have talked to some custom riflemakers who have a preference for one of the other but there's no consensus, and the differences are pretty much hair-splitting. In my experience (about a dozen .270's, and half that many .280's and 7mm magnums) any of them will shoot well under an inch if we take the time and trouble to "accurize" the rifle and construct good ammo. If we shot 1000 of each there might turn out to be 2/10ths of an inch difference between them, but what difference would that make in the field?
