sorry i ment to say 440 or 445 "popular "dont know what i was thinking
past that dont bet on the engraving thing
smoothbores have no rifling nore do they need a patch and with a proper load can hold a single hole group even at 5o yards +.
now past that . take me hershel rifle . her bore is .548 . i shoot a . 530 ball and a .018 patch . not that tight of a combow and guess what ?
the world turns .
well i seem to do ok
see the thing is , while the patch has to impart twist to the ball , it can still do that becouse the ball exspands somewhat as the pressure from the main charge slams into it.
i also use hard ball for hunting . there is very little engraving of patch material concerning them