Best to ask a gunsmith for assistance.
Browning.com has manuals you can request or download
I would contact browning arms at there web site.they have a place to date your browning firearm.
It is a Browning .22 semi automatic rifle simply called ".22 semi-auto rifle". Made in 1963. Yours is chambered for .22 long rifle cartridges
Made in the U.S.A.
Your Browning BLR model rifle was made in the year 1969.
This is a Browning .22 auto rifle made in 1968.
You will have to call Browning with the serial number.
The suffix of M73 indicates that your Browning BAR semi-auto rifle was made in the year 1973.
The suffix of M71 was assigned to the Browning model BAR(Browning semi-auto rifle) which was made in the year 1971 in Belgium for Browning.
I know that Browning made a Greywolf A-bolt rifle in 30-06 because I have one. I don't know if they made any in .270 cal. The Greywolf was only manufactured in 1994 with very limited production. I've heard that there were only 380 made. They are stainless steel with a wooden stock and came with the Browning BOSS attachment.
YOu will have to call Browning to find out. It was made in 1978
Japan