Do not want to highjack threads form other members so I began my own thread.

I have been checking advises about round ball from 12 Ga “smooth barrel rifle” and I want to be sure to buy the right RB.
I have scoped my Spanish double barrel shotgun so I can use it as 12 Ga double rifle.
BTW: I will try the filing of the muzzles for regulation.

Now my questions:
Right barrel is cylinder at .725” and left is choked, .693”.
What RB diameter would work best in both barrels?
I will order a mold from Tanner so I can get almost any diameter.
What about .690” round ball?
Would it work in cylinder barrels?

Thank you very much.
Martin