This would be a Browning BAR semi-auto rifle
All Brownings have serial numbers.
The M7 suffix to your serial number indicates that you have a browning B.A.R. that was made by browning in 1967.
Comparison to known serial numbers.
On the webste for Browning firearms, under customer service.
You will have to call Browning.
The earlier the better. 1 is in the Browning Museum.
1981
You will need to supply the serial numbers to your shotguns to get the age of your browning shotguns correctly.
The suffix of M71 was assigned to the Browning model BAR(Browning semi-auto rifle) which was made in the year 1971 in Belgium for Browning.
Please provide the model information. Serial numbers were sequential by model only.
50-500 usd
1975