10 Gauge Bore Dimensions?

[Roundsworth]

According to the 'book', my 10 gauge lifter's barrels are the original length, 32". I do not have the proper instruments to measure bores, but I did manage the following:

1) Chambers= .855" ("For the 10A or modern shells")

2) Chokes:
R= .792"
L= .796"

3) Muzzle thickness:
R= .063"
L= .065"

There is barely a 'step down' to the bore from the chamber, which to me is ideal for a thin brass case, not a thick paper shell. The modern 10 bore is about .775", isn't it? Does anyone have any idea what my bore diameter is, or was originally? There is some roughness near the chambers, but the remainder of the bores look pretty good for 131 years! I cannot say yay or nay about any honing in the near or distant past. Cheers!