That isnt a percussion shotgun. It was merely and old style break action shotgun with external hammers that struck firing pins. Most likely the barrels were Damascus steel and it IS a blessing that gun is off the street and will never be fired again. . . attempting to fire it with modern shells with modern pressures would likely cause it to explode the chamber and injure the person pulling the trigger. There is a vintage Winchester .22 pump rifle in that pile also... Looks like a model 1906. Not in great shape, over cleaned.
That’s not always true.
For the cheaper shotguns, yes, it might be true that the damascus barrels will let go.
For higher quality shotguns, their damascus can be stronger than the “fluid steel” of the day.
See WW Greener’s writings on the topic for more information. He had proofed some of his firm’s (WW Greener) damascus barrels and had the proof house feed the same loads into fluid steel shotguns of the competition, which caused ruptures.
There were several grades of damascus steel back then. Yes, there are lots of no-name Liege tubes that would probably fail, but the higher end shotguns (both American and British) of the era had higher quality barrels than the no-name twist steels out of Liege.