Comments by "" (@neutronalchemist3241) on "Clair Brothers Semiauto Shotgun from the 1890s" video.

@Ponen77 Cosmi semiauto, since 1907. They are still manufactured, but very rare. https://www.thefirearmblog.com/blog/wp-content/uploads/2020/03/Cosmi-RIGATO-Semi-Auto-Rifle-6.jpg
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@Warptenlololol It's interesting, but there's a reason if gas action shotguns didn't take off until well after WWII, while there had been a pletora of recoil operated, delayed blowbacks and so on. Shotgun ammos are ineherently dirtier than bottlenecks (go figures at the end of 19th century). Even worse with the gas port so forward in the barrel, and the gas chamber here even contains the recoil spring. I would not be surprised to know that the mechanism was locked by the gunk after about one hundred rounds.
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