How much is a browning 20 gauge 7x 805 worth?

That cannot be answered without you providing a detailed description of your shotguns overall condition including the amount of original finish remaining on the wood and metal.Also include the type of barrel with your shotgun,and bore condition.I can say that your Browning auto-5 20ga.shotgun is a magnum 20 gauge which was made in Belgium for Browning in the year 1967.