The Browning website has a page enabling you to find your shotgun's age, but you have to know the type of shotgun you own. Go to the page, then click on the type of shotgun it is - there are 15 types - and then reading the page for that gun's serial numbers. Look for the series of serial numbers that includes the one you are interested in: #48162.
2003
1977
1993
1990.
1991
12 gauge Belgian Browning shotgun, serial #296305
You will have to call Browning or provide the serial number.
With the serial number that you provided,your Browning superposed shotgun was made in Belguim for Browning in the year 1955.
Your browning 20ga model auto-5 shotgun was made by FN of belguim for browning in 1962,with the serial number provided.
You will need to call Browning.
Call Browning with the serial number.
You will need to call Browning.