I went the 6.5 route simply because I am a shooter first and hunter second. I really wanted the capability to reach out further at the range. As far as hunting goes, I think (and evidence seems to back it up) that the 6.5 grendel and 6.8 spc are about equal as a hunting round. Sure the 6.5 can shoot flatter and farther, but just because it will go farther doesn't mean you should be killing big game out to the extreme. I am taking my grendel out this morning to hunt deer with. I loaded up some 120 grain barnes TTSX with 26 grains of TAC. It should be enough to take one down as long as I hit where I am aiming. Another reason I went with the grendel is because brass can be made from 7.62x39 brass. I figured that if it ever went belly up that I would have a cheap, reliable source of brass even if they stopped making it.
The 6.5 will take better advantage of the 20-24" barrel than the 6.8 simply because the 6.8 doesn't seem to get much from longer barrels. The 6.8 is great in short barrels because it doesn't lose much in velocity with short barrels. The 6.5 really seems to shine in 24" barrels. I believe that either the 6.8 or 6.5 will give you as much accuracy as your little heart can desire so there is no advantage with either one in that department. Here is a link to the Elk that Mark LaRue shot at 400 yards with the grendel.
http://www.ar15.com/forums/topic.htm...=164444&page=2
here are some pictures of what I have done with the grendel.
left is a 7.62x39 necked down to 6.5. middle and right is the fireformed case into 6.5 grendel.
I'll have to second all that. The 6.8 is basically a .270 bullet, the 6.5, a .260, so not a lot of difference in diameter. Both have been well proven in the gamefields of North Ameriaca and northern Europe. the. .270 good for deer, elk ect. the Swedes use the 6.5 on their moose., both generally out of larger cases at higher velocities, but they both are bigger bullets than the .223.
I went the Grendel route, because I am a shooter. My rifle likes the heavier 130 gr bullets, which are fine for the heavier med and larger deer type animals.
Cartridge cost is not much. I picked up 2000 cases of 7.62x39 IMI brass and have simpely run them through a Grendel die, making sure to size well, setting shoulder back slightly, load a slightly reduced load, then load and shoot. The end result is a nicely fireformed case as pictured. I find the fireforming loads very accurate, velocity is probably a bit lower, but for fun or target shooting where the absolutly best in accuracy is not needed, they are fine. This is not to say they are not accurate because they are.
This has been my first experience in fireforming for a modern cartridge for a semi auto, and it's really quite easy and certainly keeps the ammo cost down. Keep all that in mind if you can or plan to reload. The 7.62 cases are very common.