Actually when in comes to "sizes"
there are small and large. Small measure .175" in diameter and large measure .210"in diameter. The cups of the large rifle are taller.
Each brand has many kinds look at Federal
They have 4 kinds ie with large rifle
Regular 210 and Match Regular 210M
Magnum 215 and Match Magnum 215M
and they make a 216 Magnum that is not distributed....
Whereas CCI
Has 400 small rifle, 450 small rifle magnum, BR4 for benchrest
Or Remington
6.5 small rifle, and 7.5 bench rest
Following the loading manuals is paramount!