The solder joint failed after 100 or so years. I have had it happen Certainly a routine repair for a good smith. He nay have to strip the rib clean and re-solder the lug re=lay the rib and possibly re-blue the barrels. Gunter just did a 5E NID skeet gun for me. It happens-my buddies LC had to have the same treatment.

Walter c. Snyder