Anyone consider this variant? Life starts out as a 6.5 Grendel case necked down to 6mm. I like the ease of reloading and specs.

http://www.6mmar.com/Page_1.html

The 6mmAR and all its' variants were created by Robery Whitly and have been around for a while. There is some good information on his rounds over on 65grendel.com under the 6.5 Grendel Wilcat forum.

Thanks for the link. Will check it out at 65Grendel.

Well there was a 6mm based on the 223 case or 5.56 the Marines were playing with.
Then there is the 6mm PPC (?) based on the 7.62x39 that is or was the darling of the bench rest crowd.
The 6 mmx 45(?) was a mediocer preformer while the 6mmx39 was a decent preformer with tack driveing accuracy. A lot of Ar platforms can achieve sub MOA preformance.

i read that the 6.8 can fit in 5.56 magazines. is that true? i know the bcg and barrel would be different but that would make things a lot easier on my part not having to buy so many caliber specific parts (i.e. i can use a normal upper and lower w/ the 6.8 as opposed to the 762 where its gotta be a 762 upper and 762 lower).

i also read that the 6.8mm spc cartridge isnt available to the public. is that true?

The 6.8 supposedly will fit in a 5.56 mag, but will not feed reliably. 6.8 is, of course, available to anyone. I just ordered a bunch from Cabelas last night.