Your Belgium made standard weight auto-5 shotgun which was made in the year 1947 with the serial number you provided could bring between 375-450 dollars with a plain barrel,450-550 dollars for a solid matte rib barrel,or 550-675 dollars for a vent rib barrel model.
Your question is about the Browning auto-5 shotgun.The age of your Browning cannot be determined without you providing a serial number for your Browning.
Impossible to answer without knowing which model.
No way to answer without the serial number.
Impossible to answer without knowing if it is a rifle, shotgun or hand gun.
Impossible to answer without knowing which model and its condition.
Impossible to answer without a detailed description and the serial number.
Call Browning and ask.
Impossible to value without any more information.
Impossible to answer without a detailed description of all markings, features, barrel(s) length, type of action (O/U, SxS, Semi-Auto, Pump) condition, box, papers, finish, accessories, etc.
Impossible to answer without a serial number.
There is no way to age your browning auto-5 shotgun without a serial number.As to the value,this would be 450 dollars for a shotgun in the condition that you describe.I can say that the Browning auto-5 standard weight shotgun in 16gauge was made from 1946-1964.
Can't be answered without a DETAILED description of ALL markings, finish, overall condition, box, papers, accessories, etc..