"Waterfowl" guns were certainly popular

Pre-WWI Jeffery's "Long Range" hammerless "Waterfowl" gun was available in 3" chambers that "can be used with from 4-5 drams of black powder and 1 3/8 to 1 1/2 oz. of Shot".



1920s G.E. Lewis & Sons



Major Sir Gerald Burrard, The Modern Shotgun, Volume II, “The Cartridge”, 1955 3rd Revised Edition listed the 12g 3” 1 1/2 oz. 3.57 Dr. Eq. load at Standard Service Pressure of 9,632 psi and Max. Service at 12,320 psi

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