Ironworker- Rock makes a hell of a 6mm barrel. He used to make all of Pindells 6 mm barrels. Pindell is the creater of the BR king cartidge the 6 PPC (6 Pindell and Palmisano Cartidge) Rock had the M24 sniper rifle barrel contract so he's not as well known as Krieger, Hart etc. But he is the best kept secret in the custom rifle world. I feel he produces the most consistent accurate cut rifled barrel out there. With around 75% of the 308s I build averaging 1/4 MOA and the rest 1/2 or under speaks volumes for Rock's tubes.