A friend sent me a photocopy of an 1886-7 Chamberlin Cartridge Co. catalogue. I don't know if this is new information or not, but I thought the special loading of cartridges for Parker Guns might be of interest.
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Note on the bottom of Page 7 it states that "The loads adapted for Parker Guns were formulated by Mr. S.A. Tucker, of Parker Brothers."
On the cover it states that they have the capacity to load 200000 shells daily.