Hmmmmmmmmmmmmm... that is kinda interesting, inasmuch as what is stated there " might" be somewhere near correct, but not sure if it is. The lesser listed ball diameters I readily confess I know not about. But, I do have a tad bit of experience with the larger and definitely more exciting bore sizes.
IIRC, the 4 bore rifle should have a bore size of 1.05" +/-. He doesn't even get to that, but instead starts at 5 bore, which he lists as 1.15". The 4 bore barrels of which I am most familiar with as made by Joe Williams of Oregon Barrel Company, seemed to really like a .980" ball. I seem to recall that I had been using a .990 ball but experienced a lot of difficulty loading, so I dropped down to .980 and life was much better. Remember also that "back in the day" bore size was subjective. Turner Kirkland (of Dixie Gun Works) referred to his double rifle as a 4 bore, but was much closer to a 6 bore in actual size. I think I miked the muzzle at about .890" See what I mean?
Going to bore size weight, (remember these numbers are pulled out of long term memory), I seem to recall that the .980 ball I used weighed in at approximately 1,450 grains, which when divided into 7,000 gives an answer of 4.827, which rounded would equal a 5 bore size by weight. So, I think the 1.15" diameter is way off.
And I am suspicious also about the rest of his large bore supposed sizes. I don't accept the chart as correct. And that is the kind of mood I am in today.