So I researched a lot about the brass frame stretch problems as I had purchased an 1851 brass 36 navy. I was curious if what I had tried could help benefit anyone else. That you have a good gun smith and are safe with the alteration. If someone had already thought of this and posted this I'm sorry! I had not seen it. Pic 1 shows the steel washer, as does Pic 2, and Pic 3 is to show that the arbor is straight and accepts the Barrel.