I favor using a 530 hornady RB and .017 pillow patch material in my 54 cal. barrel
I think I would start with the 530 dia: and go from there,I read a post that you have problems in buying pillow patch material from walmart in your location,I can if you like the next trip I make to walmart pickup 3 yards of the stuff and mail it to you if you like :
you can send me the funds later