Originally Posted by Parabola
It can probably restored to a remarkable extent PROVIDED YOU KEEP ANYONE WITH A STEEL WIRE BRUSH AWAY FROM IT!

Honest, and even criminal, neglect is generally much easier to deal with than the results produced by Bubba with a power tool.

I have an old box lock non ejector where someone used a file card or similar to read the markings, leaving me with the problem of getting rid of scratches that look like the plan of a railway marshalling yard whilst preserving the markings.

It is hard to judge from a photograph but the pitting in the bore looks fairly superficial. At least with Sir Joseph Whitworth’s Fluid Compressed Steel you have best quality material if you can keep sufficient wall thickness.

Are they chopper lump barrels? I believe that I can detect the joining line in the photo of the bottom of the lumps.

Glad I researched it before getting too into cleaning it up! So far I have only taken a brass brush and some oil to a few of the rusty areas, so I don't think I've bubba'd it yet... No visible scratches at least. I'll consult with an expert before going further though!
My dad said it was probably an old farm gun, likely some cheap eastern European knock-off crazy

I hope that's the case with the pitting. I don't have the tools to accurately measure, but the barrels seem pretty heavily built. In cases of superficial pitting, is there any repair that can or should be done?

Not positive if the barrels are chopper lump, but I think so - I'm new to shotguns so still struggling a bit with the terminology...
This picture shows a very slight seam in the concave cutout. That's the only area around the lumps I can see any visible seam whatsoever. Would it continue all the way through the lumps on centerline?
[Linked Image from sturdy-designs.com]