You did not provide a serial number, so, the question can't be answered.
Which model?
12 gauge Belgian Browning shotgun, serial #296305
1934
What model?
No serial number = no way to answer.
You will have to contact Browning.
Need the rest of the serial number.
The 2 letters located in your serial number(NV) indicate that your Browning gold 12 gauge shotgun was made in the year 1995.
What is the value of a 12 gauge Browning shotgun serial J68824?
It was made in 1928
If that is the complete serial number, 1924.
If there are no letters proceeding this number, it was made in 1927