Ditto...Very interesting Norman thanks,
I am puzzled - why should a rotating bolt lack primary extraction?On the CIS .50 MG, a rotating bolt gun, the lack of primary extraction inherent in that system led to hard extraction and as a result a low fire rate on prototypes.
These guns do of course use the same retarded blowback mechanism as the earlier HKsThe bedrooms of assault rifles 5.56x45 CETME 7.62 x51 and also leave those marks on the case