In a across the board comparison, the 6.8 SPC can't hold a candle to the 6.5 Grendel. The Grendel will walk all over it. Problem is people comparing the two Chamberings for the same purpose. The cartridges were designed for completely different applications. The 6.8 being right at home for CQB stuff in the "Stan" and the Grendel for the extended stuff on a platform lighter than the AR-10 or SR-25 platform. Both have their place. I have personally witnessed a one shot stop on a mature Mulie, with a 120gr BT out of a 16" Grendel carbine at 496 yards or so, may have been 493. Can't recal exactly.