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Your serial number indicates that you have a Browning BAR that was made in the year 1973 with the suffix of M73 after the serial number.
How value is Browning 300 Win Mag Semi Automatic
Yes
Value is too difficult to be accurate without seeing the gun. Condition which includes the amount of original finish and original configuration will determine value. Recommend taking it to a gun shop for appraisal.
Browning Challenger made in 1974. $300-$400.
The M69 suffix identifies your 300 win mag as being a browning BAR that was made in 1969.
50-300 usd
Markings, serial number and features.
50-300 uSD
This is really a Stevens / not Browning. These usually sell for $125-$300 depending on condition
100-300 USD
100-300 USD