Meet every argument dead center ...... 260 Remington. Logistically a single caliber for GPMG’s and Battle Rifle . Planners seem to forget past wars mistakes. Short range CQB Stopping power, long range hits / terminal velocities , human wave aggressors , replenishment, resupply common caliber.... above all else reliable , tested, proven designs to use the .260 Rem.
My choice...
Never shot that caliber. Cannot be much different from 270 which is well know and very common.
Very good deer rifle caliber.