This reminds of Big Johns Grunig target rifle. I think he spent more time poking the fired cases out with a rod than he did shooting. That was a pure match rifle and RG Black spot just didn't want to extract at all.
Well, if one uses military issue ammo in a match chamber, what can you expect?
-JMS
I have never found minimal headspacing to give the best accuracy. best accuracy was with headspace between minimum and maximum and had the files full of targets to back it up. ~Muir