Beretta 3901

The Beretta AL391 Urika is a semi-automatic shotgun manufactured by Fabbrica dArmi Pietro Beretta in Italy. It uses a gas-operated action and features Berettas rotating bolt design. The AL391 was introduced as a successor to the popular AL390 series. It is chambered in 12 gauge and 20 gauge and was offered in multiple configurations including field, target, and tactical models. The Urika features an anodized aluminum receiver and a Kick-Off recoil reduction system on some variants.

The Winchester Model 40 was a prototype semi-automatic shotgun developed by Winchester in the 1940s. It was designed to compete with the Browning Auto-5 and Remington Model 11. The shotgun used a unique gas-operated system and was chambered in 12 gauge. It was never mass-produced and only a small number of prototypes were made. The Model 40 remains a rare piece of Winchester development history.

The Browning B-2000 is a semi-automatic shotgun produced by Browning Arms Company. It uses a unique gas-operated system with a floating chamber design. The shotgun was chambered in 12 and 20 gauge. It featured a distinctive streamlined receiver and an adjustable gas system. The B-2000 was produced for only a few years and is relatively rare.