You should NOT shoot a damascus-barreled gun, even with black powder shells.
When a damascus barrel is made, it consists of several "bands" of steel which are pounded around a mandrel, then welded together, then re-shaped and polished smooth again. Unfortunately, within the barrel bands themselves, oxygen is trapped as the welding takes place and, eventually, especially with a strain inside the barrel like a shell being fired, the barrel tends to break or split open under pressure where the oxygen is/was trapped.
In the old days, you would see men out in public with the first joint or two of the first 3 fingers of their right hands missing where that hand wrapped around and gripped a shotgun barrel. This was often due to having the barrel or barrels of a damascus-barreled shotgun burst upon being fired... and the man's fingers were blown off.
Oddly enough... a shotgun with a damascus barrel can fire shell after shell, then... SUDDENLY "let go" and explode... knocking a "chunk" out of the barrel near the chamber.
Just make SURE you are NOT one of the "victims".
Strength & Honor...
Ron T.