Ok, here we go, hope these help
1/. close up picture of the seam running from 12 o'clock towards 6 o'clock
2/. Side view of ball, flat spot is too the right hand side of the image, ball appears thinner than taller
3/. close up view of the flat spot, the flat spot appears more pitted than the rest of the ball, to my mind that would occur under explosion of ignition, but open for correction quite happily. (looks like the moon)
and last but by no means least
4/. looking directly at the rifling from rear point of view, now this is what i have seen, and would love to know what you guys think.....
does it appear, starting from a groove and moving counter clockwise that the curve of the land falls in before the next groove, and then steps up again before falling down slightly again as the process repeats itself?
could this be a centrifugal force being evidenced?
and as a final note, whilst strolling for hours last night i found this page on the net that describes old rifled muskets for sale, that describes each weapon in detail, and as you go through them, the number of rifle grooves varies according to the private small maker.
http://www.thomasdelmar.com/Catalogues/as121207/page19.htm