Browning never used the letter B prefix to there serial numbers.
You will have to call Browning.
Not a valid Browning serial number.
Your serial number indicates that your Browning auto-5 shotgun in 16 gauge was made in the year 1937.
With the serial number that you provided,your Browning 16 gauge shotgun was produced in the year 1949,by FN of Belguim for Browning.
You have an Amwerican Browning made by Remington for Browning during WWII. It was made in 1947.
Your serial number indicates that your Browning auto-5 16 gauge shotgun was made in the year 1948.
Your Browning auto-5 shotgun in 16 gauge was made in the year 1930,with the serial number that you have provided.
Your serial number indicates that your Browning auto-5,12 gauge shotgun was made in the year 1949.
your browning sixteen gauge auto-5 was made in 1954.
With the serial number that you have given,your Browning auto-5 shotgun in 16 gauge was made in the year 1937.
Your serial number indicates that your Browning auto-5,12 gauge shotgun was made in the year 1949.
While you do not state what gauge your browning auto-5 shotgun is in?I can say that if you have a 12 gauge model it was made in 1927.If you have a 16 gauge then it was made in 1930.based on the serial number that you provided.