The value of your Browning BAR which was made in 1970(M70) is between 450-650 dollars,depending on overall condition,and a good bore.
100-1000 usd
500 USD
AFAIK, Browning didn't make any rifles in that caliber.
-80-800 usd
500-800
100-1000 USD or more
200-500 USD depending on condition.
No.
500-800
100-1000 USD
Browning.com has a sn function under customer service.
Yes, the A Bolt was made in 338 RUM.