50-750 usd
A browning safari grade rifle in a standard caliber,and the condition you describe is valued at 995-1,100 dollars.
Yes
$150 - $400 depending on condition and year made (barrel markings determine the period when the barrel was made)
About $300-$400 depending on condition and barrel configuration.
100-1000 USD or more depending on specifics.
your 1953 browning sweet sixteen if it has a plain barrel would be worth between 500-950 dollars depending on condition,if it has a vent-rib barrel it would be worth between 775-1300 dollars again depending on condition.
The "rate of twist on rifling" is caliber specific. To give you an answer we would need to know which cartridge the rifle is chambered for.
If you have a standard barrel then 525 dollars,if you have a vent-rib barrel then 735 dollars.You made add 40% to the above stated prices because you have a 20 gauge model.
The browning auto-5 shotguns are going for anywhere from 375-650 dollars depending on condition.
500 or so
You did not provide a detailed description of the weapon, its features, finish, condition, box, papers, any accessories, barrel length, sights, etc.. The best I can do is a genearl price range. You might be in the 300-1000 USD range, give or take.
If in "new in Box" condition it will bring $1300-1500