Both the civilian sporting rifle and the military light machinegun that go by the name BAR have barrels that are not removable by the user. They require special tools to remove them without damaging the receiver (frame).
The website for Browning Firearms has a downloadable owner's manual that covers assembly/ disassembly, and it instructs the owner not to attempt disassembly beyond the point listed. Normal cleaning and maintenance is performed while the barrel is attached to the frame. If you want the barrel replaced, you need to visit a gunsmith with a set of action blocks and a barrel wrench.
Leave this to a gunsmith
Marked on the barrel.
Look on the barrel/receiver and it will tell you.
Yes
Your browning model BAR which was made in 1985 should say either made in belguim on the barrel,or made in belguim assembled in portugal on the barrel.
Check with Browning customer service.
You can go to Browning.com and download a BAR manual.
Best to ask a gunsmith for help.
Follow the instructions in the A5 manual using the link below.
Open action remove pin remove slide,barrel,spring.
you first begin by standing the gun on it's butt compress the barrel downward and loosen then remove the nut on the magizine and remove the forarm you then remove the barrel by getting a firm grip on the barrel and pull it off you can then remove the frictoin rings and spring
Best left to a good gunsmith