As Dick has mentioned, unless the barrels wall thickness has been measured and gun totaled inspected, I would wait to shoot it. As you mentioned "heavily pitted" I doubt if they were honed out. You didn't mentioned what type of barrels it had. At this time there was Royal Steel, the cheapest barrel made because it was fluid steel and not Stub Twist or Damascus.
If it were mine I would load up some low velocity, low pressure loads, and shoot them in an area where you can find the wad. Look at the wad, if it is not badly chewed around the seal and petals part, I would shoot it with those loads. The reason for this, if there was deep pitting, the wad would try to conform to the irregularities of the barrel and if deeply pitted, it would try to go into those areas and chew it up.
I would be concerned if the barrels did not have any pitting, meaning they were honed out.