Of course! It's a bigger, heavier bullet that travels only slightly slower than a 223, it also costs about 5x as much to shoot it, if you are thinking of building/buying an AR stick with common cartridges. 223 is a great varmint cartridge if that is what you are thinking of using it for and in general if you can't kill it with a 223 then you have no business shooting it with a 6.8, yes you can use a 6.8 for deer but a .243 would be better.