what is your question?
Up to 1000 USD
Impossible to value with only a serial number.
50-5000 USD or more depending on specifics.
0-500 USD depending on condition.
200-2000 USD depending on specifics
It has not been made yet.
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.
No way to price a weapon with just the serial number and no description.
Browning did not make the Model 70, Winchester did. Also, the serial number is not a valid Browning serial number for a 7mm Magnum rifle. Please doublecheck your information.
You did not give the sn. Call Browning.
Sometime in the 80s. You will have to call Browning to narrow it down further.
Which model?