Quote Originally Posted by tr63 View Post
It should not close on the .308 No go gauge !! Your head space is off !! Sarco .308 barrels are short chambered . Historic Arms rewelded the receiver and did not allow for normal bolt and locking shoulder set back and that why you have incorrect long head space . There are many Historic Arms Bren's with all kinds of problems which head space is one . You need to change the the locking with a large/longer one to correct the head space so that the bolt will not close on the no go gauge and the cases should not separate.
It is NOT a sarco barrel. It is an original UKicon 7.62x51 which if I'm understanding correctly may still close on 308 no go without issue. It wont close on the 7.62x51 max gauge.