Would like to know knowing the quality of good condition Krupp steel barrels and what kind of loads they were designed to shoot.
They will handle the same loads as a good set of damascus barrels made for a similarly proofed gun.
Krupp did not a magical ability to produce steel barrels for pressures that would not be in common use for decades.
Find a good smith and have them check the entire gun. While you may have faith in those barrels has any one checked the receiver for internal cracking or the stock for splitting? I recently purchased an old beater for a project. While the gun showed it's age and heavy usage, once the receiver was taken down, there were at cracks in the wood that were not visible othewise.

Pete