If one were to make the wrist round at a 1-5/16" dim., it would be correct. Also, adding 1/32" to the width would be correct and possibly help w/ the carving and appeal.
The wrist dim. somewhat depends on the trigger guard....a shallow bow should have a smaller vertical wrist dim. I've settled on the Reeves Goehring #47 which actually is a Verner TG, but I modify it w/ thumbnails on the ends of the front and rear finials. It has a slightly deeper bow VS a widely used TG that is offered by a few suppliers.
Below are 3 pics of 2 BC LRs that have the 2 different TGs....the top pics are that of the Reeves Goehring TG and the bottom is that of the widely used TG. Both have the same vertical wrist dim.
To get a slender and typical BC, the web at the breech is 3/32" and 5/32" at the muzzle. The transition form the lower forend to the wrist is very important and thicker webs causing deeper lower forends don' t contribute to the look of a BC.
I don't consider myself an expert on BC LRs so take my info as "unsubstaniated" and use it along w/ a whole lot of other info.
Just added the Reeves #47 TG w/ the thumbnails filed on. It's on the top BC.