The 72G prefix indicates that you have a browning auto-5 light weight shotgun that was made by FN of belguim for browning in 1972.
You will have to call Browning with the serial number.
You will have to call Browning with the serial number to find out.
The Browning Auto-5 with serial number 103987 appears to be from the early production period, most likely before 1940. However, the serial number by itself isn’t enough to pin down the exact year because Browning’s records for early Auto-5s are incomplete. I’d recommend checking the complete markings on the receiver and barrel, including any letters, proof marks, gauge information, and whether it was made in Belgium or elsewhere. Those details can help narrow down the date much more accurately. Browning also notes that early Auto-5 production dates are sometimes estimates because very few records from that period remain.
Your serial number indicates that you have a 16 gauge Browning auto-5 shotgun that was made in the year 1951.
Your serial number indicates that you have a Browning auto-5 Magnum shotgun that was made in the year 1965.
On the receiver.
A Browning Auto 5 Lightweight shotgun was made in 1957 with that serial number on it.
Your Browning auto-5,12 gauge shotgun was made in the year 1948,with the serial number 265,711.
The prefix to your serial number of 70z indicates that your Browning auto-5 shotgun was made in the year 1970.
You must call Browning with the serial number.
No serial number provided.
No way to answer without the serial number.