The Model 1941 Sosso is a huge Italian experimental semiauto pistol designed by Giulio Sosso. It uses a short recoil locking mechanism and is chambered for standard 9x19mm Parabellum ammunition, but its more unusual feature is its magazine. Instead of using a traditional spring and follower, the magazine body holds a 21-segment chain, like a machine gun belt. The chain is rotated one position each time the pistol's slide cycles. This would prevent problems related to magazine spring fatigue or varying pressure between the first and last round, but it also introduces a whole new set of potential problems.
Only 5 of these pistols were made (by FNA Brescia), with the other 4 of them being presented to significant Italian political and military figures. It was not adopted or put into any sort of serial production for reasons that should become very clear once the internals of the gun are seen. One could probably buy a dozen Beretta 1934 pistols for the cost of one Sosso...
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