I think it would be possible. The only problem I can forsee is the the integrity or "hardness" of the weld material. I'm not sure how well the added on material/metal would hold up with continued use.
I've wondered if this would be an option for worn ratchets on extractors. Since they are not making new extractors for the older models many of us are still shooting, I think we are soon to find out.
I have used Micro Precision Welding before with good results, but not for repair of a worn hand.
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