I'm not concerned with value here, but I am confused.
Here is an FM made, John Browning 5, with no bluing. Serial number indicates early 1954 manufacture. There is some pitting on the receiver, visible in the picture, but no rust anywhere else. I thought all auto 5s were blue, but how could anyone get the blue all off, like this one is?
There is no sign of taking the bluing off by mechanical means, except the receiver seems to have been polished, likely in an attempt to remove the pitting.
Any suggestions?
Also, was the solid rib usual?

Here is an FM made, John Browning 5, with no bluing. Serial number indicates early 1954 manufacture. There is some pitting on the receiver, visible in the picture, but no rust anywhere else. I thought all auto 5s were blue, but how could anyone get the blue all off, like this one is?
There is no sign of taking the bluing off by mechanical means, except the receiver seems to have been polished, likely in an attempt to remove the pitting.
Any suggestions?
Also, was the solid rib usual?





















































