The 6.5 Grendel in either a bolt gun or an AR will be very hard to beat.
Shooting .264 caliber bullets of modest weight makes the rifle capable of harvesting most North American game and the low velocity keeps the recoil down to the same level as the .243 Winchester.
In today's world, trajectory is not as important as it once was because we will almost always use a laser rangefinder when the target is further away than 200-250 yards. This means that the same effort is needed to get the right holdover regardless of cartridge. The heavier bullets in the Grendel tend to drift a bit less too.
You can read more about this and a neat
Grendel Reloading Handbook and more about
medium game hunting with the Grendel by selecting the highlighted text.