Day in and day out the 7RM is faster across the board if both are operated at the same pressures....in general 7RM will move a 160 gr bullet at the same velocities a 280 will move a 140,as a general rule.And a 7RM will outrun the 280 pretty easily with the same bullet weight.By how much depneds on how hot you choose to load each catridge, what barrel you are running, etc etc.
I always looked at the 280 much the same as a 270,a cartridge for a light and lively mountain rifle weighing in the 7-7.5 pound range with a 22" barrel;and the 7 mag weighing a bit more with a 24"+ tube. If I'm gonna lug a 24" tube I would just as soon have the magnum chambering and take advantage of the additional powder capacity.
Differences in recoil between them are pretty moot to me,as even a heavily loaded 7RM's recoil is trifling....this has always been one of the cartridges greatest virtues.
