German Becker Revolving Semiautomatic Shotgun
This unusual shotgun was invented in 1899 but for unknown reasons (to me) it was not produced until early 1920's in Germany. Only around 100 of the these were ever made by the Römerwerk Suhl. It was tested and approved by DEVA Deutsche Versuchs- und Prüf-Anstalt für Jagd- und Sportwaffen or by then known as the Deutsche Versuchs-Anstalt für Handfeuerwaffen. DEVA was an independent organisation for proofing and examining new firearms and the transition to smokeless powders, to assure their safety. The shotgun invented by Becker fires a 2-1/2" 16gauge shotshells which are loaded through a port on the right side of the receiver into a 5-shot revolving cylinder. As the chambers are loaded, the cylinder is rotated until all five chambers are filled. The barrel is pulled forward through the handguard which cock the first shot. (see Picture showing the springs inside the handguard) Then, when the safety is released and the first round is fired, the barrel automatically recoils forward, locks and the cylinder rotates ready for the next shot. For each shot fired it ejects the empty cases with an automatic ejector rod.
Photos and information from: Cesare