The Cosmi is a very high-end boutique Italian sporting shotgun. It has all the looks and lines of a single shot break-action gun, but hiding inside is a long recoil self-loading action and 8-round magazine tube.
The video I have today is really only half a video – I filmed this footage back in the summer of 2015, anticipating that we would pair it with some footage at the range using the gun. However, when we got out there, we realized that we had the wrong recoil spring for the ammunition on hand, and the gun wouldn’t cycle reliably. I have not had another opportunity to film a Cosmi since, so I figured I might as well post this much to give at least some information on the mechanism. I do plan to film a complete (including much better disassembly and explanation of the mechanism) video on the Cosmi, but I don’t know when that will be feasible.