Came out in '67,,,made in Belgium til '76. After that, the parts were produced in Belgium but the rifles themselves were assembled in Portugal. The barrel markings will make note of the change. The '67-'76 Belgian guns will have an 'M' followed by a 1 or 2 digit number code for the year of mfg in the serial number and they restarted with ser#0001 each year during that time IIRC. Not sure what they did during the later assembled guns.
All were drilled and tapped at the factory for scope mounts.
Brownings 'salt cured wood' problem starts around '66 production and is seen most often in the O/U shotguns though it can be found in any of their models in that time period up to around '76/78.
Mostly high grade wood used on 'graded' guns was affected.
Plain rock salt was used to draw the natural moisture from the uncured wood in what was thought to be a quick way to cure the wood instead of having to wait months/years for it to air dry for use.
It impregnated the wood with salt as the moisture was drawn out and to this day the wood will rust the metal parts of the gun as it still draws moisture back into it as any hygroscopic salt will do.
For many years Browning would replace the wood on these 'salt guns' guns, but I don't think they'll do that anymore.
There have been many tricks written about to block the rusting from occuring but none are 100% and it will reoccur,,humidity has alot to do with it of course.
The damage is nasty and goes on inside with usually only a hint of rust usually seen along the wood/metal line visable. It is salt water pitting.
That small line of rust and the attempt to remove a butt plate wood screw are usually the first things that draw attention to the problem. The butt plate screws usually twist right off at the head as the shank is rusted and eaten away in the wood from the salt.
Close examination of the metal/wood line for rust,,,,suspect a of a reblue,,,a very close examination on the high grades are things to watch for salt wood.
To each his /her own though.
