Barrel extension screw
 

Was this screw always engraved to match rib matting? If it is submerged, does this indicate rib extension came loose and/ or has other problems (solder failure due to hot bluing)? Was a filler placed over the screw and then engraved? This might explain a submerged screw head.

No Hugh, they weren’t all engraved to match the rib matting except that the standard practice for hammerless guns was to file the screw head to the same contour of the rib extension and run the matting right over the screw head.
I haven’t seen or heard of this screw being “submerged”, whatever that may mean.

On hammer guns that lack rib matting the screw head was usually engraves in some kind of floral design.



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Looking at the pics,I think now the screw may be proud of the hole.I wonder if the rib extension may have been worked on but not entirely finished.Dean ,have you seen this?By "proud" I mean sitting slightly above the barrel rib surface,readily noticable.BTW,nice bernard barrels.

No Hugh, I have never seen what you describe, that I can remember.
If you have one like that can you post a picture or two?





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There is physically no way that the extension screw can back out on its own. It is screwed down tight, then the head machined off flush the the rib to eliminate the slot and then everything is soldiered in place. If something is amiss, then it has been fooled with. Maybe the extension replaced or repaired.

I think you are right.May pass on this one.Thanks Brian and Dean.

I will add that I have seen where the extension is bent up from the breech due to damage of one sort of another. And the screw will be lower than the rib in that case. And of course the dolls head will be standing up from the frame as well as the solder joint broken.