Barrel ribs only lift when there is a build up of rust under the ribs the only cure is to remove the ribs and part the barrels to clean , Check the barrels to see if loaded then remove the breech plugs clean and lap the bores to a good finish also any pits and reassembly. You will find on 99%of English made guns that the ribs are soldered but on some Belgian made they are brazed
Also remember when doing restoration a gun that is 150 years plus should look its age and not something straight of the shelf, another thing always stick too the original and not add extras to it such has carvings , brass inlays and black or blue barrels Enclosed are images of one of the many gun restoration which can be saved and brought back too life and not gone for scrap.
Feltwad
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The Finish Job
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