You will have to provide the serial number to date it. You can see sn tables at Proofhouse.com
Your gun is a Standard Weight model made in 1961. The suggested retail price when new was $134.50 with a plain barrel - $154.50 with a vented rib barrel.
Your browning auto-5 shotgun in 16ga. Was made in 1922.
Incomplete serial number. Value from $500-$1000.
100-350 USD
Please go to the following link: http://wiki.answers.com/Q/What_is_the_value_of_a_Browning_Sweet_Sixteen
Blue Book of Gun Values; Browning website under customer service
No.
Browning.com has sn data under customer service. You can request a factory letter for @@ 40 USD>
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. Auto 5's with recoil pads (other than Mag 12's) poly-chokes and compensators will reduce value. Recommend taking it to a gun shop for appraisal.
The vent rib breaks up the heat waves that rise from a hot barrel which interfere with sighting.
collects dirt, may come off
Best left to a trained gunsmith.