The 16g shotgun load is the standard continental 1 oz. 2 3/4 Dr. Eq. (1220 fps) and the pressure of that load would have been about 8500 psi. I did not see a chamber length mark.



28.3 grams shot = 1 oz.
2.5 grams "Schultze" = 38.5 grains
The original "Schultze" was 14 grain/dram = 38.5/14 = 2 3/4 Dr. Eq.

Brian, the guns appears to be very well used and please do not attempt to shoot the gun until it has been evaluated by a drilling specialist