what is the value of the volunteer belknap single shot 16 gauge
What is a single shot pump?
what is the value of a double barrel Newport shot gun? what is the value of a double barrel Newport shot gun?
what is the value of browning sweet 16 shot gun
That depends on the model number, age, and condition. All of those will significantly affect the value.
What is the value of a Stevens model 940b 16 gauge single shot? And when was it made?
50-165 or so
depending on age and condition, from between $250 and $450.
50-250 USD or more depending on specifics