Quote Originally Posted by jmoore View Post
That still doesn't make a lick of sense to me! It appears the LH lug fracture passes through the entire structure, either originating or terminating at it's outboard side, rather than it's root. There ought to be no load concentration there. IF it's the fracture terminus, then it's at least slightly conceivable. But then the question arises- From whence and when did the failure originate? Peter Laidlericon's comments seem worth investigating, if possible.


Brian Dickicon's example, on the other hand, is quite "textbook". Very nice! No fault of the design, just the operator/reloader.
Looks like the fracture started at the base of the main lug/rib, which is quite a massive structure, then propagated down into the small lug. I expect that the steel crystalline structure is not uniform in an Enfield bolt, as the lug faces at least will have some form of work hardening in addition to whatever manufacturing treatment they received. Perhaps that why the fracture has left part of the lug face attached, and has gone through the middle of the lug instead?

Must have been a tremendous overload to achieve that effect....