Have you looked this over Joe?
http://www.lcsmith.org/faq/faqhome.html

Esp. http://www.lcsmith.org/faq/loads.html
The Western Super-X 2 9/16 inch 16 gauge with 1 1/8 oz of shot was introduced in 1923.

A correction is pending regarding vintage 16g load pressures:
1 oz. 2 1/2 Dr. Eq. BULK Smokeless (1165 fps) was about 7000 psi;
2 3/4 Dr. Eq. (1220 fps) about 8500 psi.

BTW: Hunter Arms began correcting the stock design deficiency by 1940 and thickened the head strips for more surface area in contact with the action. This is a 1945 16g FW.



The cracks at the apex of the lock inlet start at the head of the stock; both strips cracked and stock split down the middle frown

1921 16g FW



More information regarding 1940s 16g loads here mostly courtesy of David Noreen
http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=341122&page=all

https://sites.google.com/a/damascusknowledge.com/www/home