Gunsmithing TL3 dlc bolt head headspace issue??

[SPAK]

Tl3 guys need some help. I have two standard TL3 bolt heads, one is brand new DLC coated, the other is CrN. I have loads made up for the CrN bolt head that chamber just fine. If I swap the bolt head to the dlc one I can barely close the bolt and the case head has swipes on the back like the headspace is waaaay too short. I assumed that the specs would be the same and I wouldn’t have any issues with headspace. I can’t appreciate any dimensional differences with the tools I have on hand.

i sent an email to bighorn but was wondering if any of you have any insight on this.

To be clear, I’m only swapping bolt heads and not bolt bodies.

Thanks in advance.

 

[gnochi]

DLC is a couple microns thick. I’d call Bighorn; might be an out of spec part.

 

[SPAK]

Thanks, need to mic the parts and see. In order for the dlc bolt head to chamber a round properly I need to bump shoulders back roughly .003-.004”. Which in the end is not bad, but a little less than ideal.