GunDoc,
Damned if I know, because I've never messed all that much with either version of the 6.8 SPC, mostly because it never seemed like a real solution to any hunting "problem" I've encountered--and I'm primarily a hunter.
But that's what I hear and read from people who have, and I know some SPC experts. But from other experience, suspect the twist is FAR behind the throat dimensions.
As mentioned earlier, do know that Bill Wilson (who I hunted with using his 6.8 AR's almost a decade ago) decided to develop another round that he's pretty sure works better for general big game hunting in an AR-15, the .300 HAM'R. He's pretty sure because of shooting hundreds of pigs, and other animals, with it.
Thanks for the reply. I've never explored the AR platform as a hunting rifle. But fighting bad guys, trying to kill multiple pigs at a time, or any other reason for quick repeat shots, the platform is a good one. I'm certainly not going to fault anyone for hunting with one using it within the limits of whatever the cartridge happens to be. (You have written some thoughtful stuff about the logical inconsistencies in the arguments some people use when discussing various rifle actions.)
My big issue is the government not banning the platform!
