Hi
To update the known pre 26. I have one of two made in 4 1/2 and one made for Elmer Keith in 4 inch. Two answer 410 bore. I think we can account for about 5 of the 5 inch. There were 9 made in 5 inch pre 25's
and one made in 5 inch and 4 screw. I have both of those.
Jim