The claim is that the Roper shotgun was the 1st repeating shotgun to use cartridges. The screw on (not screw in, as Jani correctly points out) choke was a bit later. The gun pictured in the auction does not appear to have the Roper choke device.


Here is Sylvester Ropers, 1868 with another of his inventions, the steam carriage.


Pete


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