Screw the AR platform...I wish there were bolt guns available in the 6.8!
I thought CZ made (or makes) one in the 527. Remington tried to sell them but without a whole lot of luck, I think. TC sold Contenders, but also sells 7-30 Waters, which is similar.
It might fit in a Vixen. That would be handy.
Edit: Checked GB. No bolt guns, just ARs and Contender barrels.