Post #7 "... one of a kind automatic revolver ..."
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https://www.rockislandauction.com/detail/62/1589/unique-experimental-semiautomatic-pistol
Rock Island Auction
Lot 1589: Unique Experimental Semi-Automatic Pistol
Sold for $2,875
CNB summary: The "cylinder" is described as a rotary magazine like the Mannlicher bolt action rifles. The pistol is an unlocked blow-back self- or auto-loading action, the barrel and bolt/slide assembly recoil together, the fallen hammer and its mainspring are used for resistance but the hammer must be manually recocked to fire the gun (kinda like the Spencer lever action rifle). This mystery gun is "... pictured on page 192 of the "World's Guns" catalog from Golden State Arms, circa 1958, the catalog lists it as being "of unknown origin"."
And as the Wizard of Oz told Dorothy: "I don't know how it works! Good-bye, folks!"