the barrels will have a heavy twist , fine Damascus is also know by some as thumb print as it looks much like that in pattern .
Do not sand blast the barrel , either send it off to a good restoration person OR carefully remove as much rust as you can and see how bad the barrels are pitted . if the pits are not to deep you can draw file the pits out and then re brown , you pattern should come back out .
I will also say I load BP paper shells and shoot to old Damascus BL I have a lot , very enjoyable. the barrels on the two i have are mostly free of pitting and very bright, with solid breeches when closed . i also only shoot BP not low base smokeless. those old guns have a sprit of their own and feel nothing like we have today , treat them with the respect they have earned with age and if any doubt have it inspected or give it a place of honor up on the wall.
Now if the barrels are browned , you can re brown them or even re rust blue them if they are of that color .
Very nice piece , well worth saving
here is a photo of Damascus twist and fine Damascus
sometimes after use and alot of cleaning the pattern disappears, Mr, Brockway made a good post in i believe my daisys double post on how to get that pattern to show again. if you are set on cleaning yours up yourself get his book and follow the barrel preparation instructions .
I would never ever cut the barrels down off unless you plan on restoring it to shoot and if thats the case then have them sent of for inspection and only cut them off if so deamed by the person you sent them to . also only shoot BP unless they are lined for smokless powder
TWIST
FINE
there is also chain ,star, and barnard patterns
BARNARD
CHAIN
STAR