Deadeye: I think your comment "... when you leave flat tops on
V cut checkering it always looks like the cut hasn't been
finished, which it hasn't. " is true when applied to modern arms and some British arms. I'm sure it is also true to you when you look at a gun.
From what I have read and seen, it is not necessarly true for longrifles made 150 years ago.
Some of the rifles made by Melchior Fordney (Lancaster Pa) in the 1830-1846 period look to have checkering which is not fully pointed, and definatly is of the V shape. (Ref
Gunsmiths of Lancaster County by Dr James B Whisker pp97-102 and
The Kentucky Rifle by The Kentucky Rifle Association 1967 pp 32-33.)
:imo: In these photos, the highlights in the checkering could have only been caused by V shaped grooves.
IMO there were several gunsmiths back then, who seemed to use checkering as a form of decoration rather than the functional grip enhancing feature we think of today.