Talk to Karl at Feldkamp Customs.
Here's my 223 he did. He fluted the bolt and barrel. It's either a 20 or 22" Rock barrel. Cant remember atm.
He also did the straight flutes on the 308 Obermeyer you see in some of the pics. That turned out great as well (flutes are really short because the barrel was fluted for an eventual overall length of just 18").
Karl said the spiral fluting on this 223 barrel was the most aggressive twist he's ever done on a rifle. I believe he said it was twisted 720 degrees IIRC.
I plan on posting more pics once my XLR chassis comes in.