With the serial number that you provided,your Browning auto-5 12 gauge shotgun was made by FN of Belguim for Browning in 1947.
With the serial number that you provided,your Browning auto-5 shotgun was produced in Belguim by FN for Browning in the year 1951.
With the serial number that you supplied,your Browning 16ga auto-5 shotgun was made in the year 1948.
See the Browning website- customer service. Date of prodcution by serial number listing.
ojn the bottom of the receiver
automatic 4 shot serial number is 1kg182.