6.5 Grendel vs. 5.56: Which AR Cartridge Is Better?
Same platform. Very different results.
The 5.56 wins on price and range versatility. The 6.5 Grendel hits harder, reaches farther, and drops deer at 400 yards. Your AR, your call.
See the full breakdown in "6.5 Grendel vs. 5.56: Which AR Cartridge Is Better? https://ammo.com/comparison/65-grendel-vs-556