I'm with Bruce on this issue, but it is important to note that the 1886 catalog refers to Black Powder which would have pressures about 2/3 of period Bulk Smokeless (in general use by about 1895).
These are the best actual Smokeless/Nitro pressures reported from turn-of-the-century studies
1 oz. 2 1/2 Dr. Eq. BULK Smokeless (1165 fps) was about 7000 psi
1 oz. 2 3/4 Dr. Eq. (1220 fps) about 8500 psi
I don't have data for Dense Smokeless which would be 1000 - 2000 psi higher
Frederick Toms,
Sporting Guns and Gunpowder, 1897
https://books.google.com/books?id=inQCAAAAYAAJ&pg=PA132
Average pressure of Nitro Bulk powders; all 3 Dr. Eq.
16g 1 oz. – 7,784 psi
20g 7/8 oz. – 10,840 psi
https://books.google.com/books?id=inQCAAAAYAAJ&pg=PA158
2 1/2 Dr. Eq.
16g 1 oz. - 7,448 psi
20g 1 oz. - 9,195 psi
These are the 16g RST numbers that I have, from 2016
Ultra Lite 2 1/2” 3/4 oz. - 4600 psi
Best (2010 - replaced by Falcon) 2 1/2” 7/8 oz. 1125 fps, 7720 psi
I don't have the 1 oz. psi but RST is quite happy to provide the numbers
The Federal Game Load 1 oz was tested by Tom Armbrust way back in 2001 at 9160 psi
Nice that we no longer have to guess (or make stuff up
) when asked "What loads were recommended for my gun?"
More U.S. maker's load recommendations are down about 1/4 here
https://docs.google.com/document/d/1...UOZEFU/preview
Long shells in short chambers about 1/3 down here
https://docs.google.com/document/d/1...vwLYc-kGA/edit