nialmac, give shimming its due. It is not elegant, but is mechanically the same as building up the hook with weld or dove-tailing in a new piece of metal. There a many metals available in shim thickness and suitable for a shim and several adhesives that are suitable. Done well, it is a pretty good solution.
The problem with all hook build-ups is that the pin may be out of round; for sure it will be slightly out of round. A new pin and fitted hook cure this ill. Otherwise, you are stuck with only part pin to hook contact. However, pins can offer some challenges.
Generally, that which is threaded in will thread out - sometimes only with great effort, though. That which is pressed in will press out; sometimes only with a serious press and blocking. That which is machined in is pretty well there to stay; see above.
One of the heavy hitters is determining just how much money/time you are willing to put into any given gun. A high value gun will merit a lot of money and/or time. A farmer grade BLNE may well be worth no more than a shim; most any gun is worth shimming, though.
