I don't understand your math Jon
If we expect the end-of-chamber WT to be .090" (or greater) and it is now measured at .065" that would be .025" less, or > 25% less.
.020" in the distal 1/3 of the barrel is IMHO not an issue (other than dent risk); inadequate end-of-chamber WT is an entirely different risk.
Not having much luck regarding the barrel steel used on the No. 3 in the 80s.
The No. 1 was reported here to have "Chrome Nickel steel" in 2008
https://www.thefield.co.uk/reviews/review/aya-no-1-shotgun-review https://www.thefield.co.uk/news/aya-no-2-20-bore-de-luxe-46431 2021
The No. 2 has Bellota EC4 = British EN8 = AISI 1040 - 1045
The No. 1 Bellota URKO-035 AISI 4135 Chrome Moly (not Chrome Nickel), steel shot proved at 1370 BAR
https://mecanizadosespeciales.com/ACEROS.htm In general, the No. 3 was a game gun. What is the overall weight?
