The 'Black Powder Era' mostly ended after DuPont introduced their Bulk Smokeless in 1894

Black Powder Pressures:
3 dram / 82 grains 1 1/8 oz. (1200 fps) is about 5000 psi.
3 3/4 dram GOEX FFFg with 1 1/4 oz. (1240 fps) is about 6000 psi.
4 drams of FFF (about 108 gr) with 1 1/8 oz. (1420 fps) is about 7000 psi.

“1895 Smokeless Powders For Shotguns”
http://books.google.com/books?id=Wv0MAQAAIAAJ&pg=PA446&lpg
3 1/4 Dram/40 grains DuPont Bulk Smokeless 1 1/8 oz. = 7440 LUP
3 1/4 Dram/44 grains “E.C.” Bulk Smokeless 1 1/8 oz. = 7584 LUP
Note: Piezoelectric transducer measurements would be about 10% higher.

The 1963 George Herter “Reloaders Handbook” lists 23 grains (3 1/4 Dr. Eq.) of Infallible Dense Smokeless, now Unique, with 1 1/8 oz. shot in a paper case with paper wads (card & fiber) at 8,725 psi by LUP, or about 9,500 psi by modern transducers. (Courtesy of Mark Ouellette)

1902 Logan-Gregg Hdw. catalog Davis guns
"Choke bored for smokeless or black powder"


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