Pulled out two parts of a horrible, horrible looking take down shotgun. Dirty, dusty, dust bunnies, scratched, dinged. Said he had got it, couldn't get it together or to work and would I take a look at it.
It is a Ranger model 30. Big whoop,that tells me a lot. But, according to the internetz tubes, it really is a Stevens model 520a, manufactured between 1912-1932. Take down 12 gauge, single bar pump action. And one infamous for not having the trigger disconnect.
Looking at it, I suspect it had been wrapped up and put away a good part of that time. Dad said he got it and was told it was missing parts.
But still, it locked together tight and while really ugly, it still looked functional. That doesn't matter to me, I'll take 'working' over 'pretty' any day.

What it looks like disassembled. You can see the very high ugliness factor.

After a cup of coffee and a partial cleanup, I think I found the problem. And that is the problem. Looking around the 'net, replacement transfer bar is forty some bucks, *if* it's available. All the sources I found, they had a listing, but none available.

Well, it's broke, I can't make it any worse. MIG welder, aluminum backing plate, had another cup of coffee and made some test runs.

OK, after the die grinder and belt sander, not looking too badly. Lay some metal on, shape, do it again.

Really wish I had a TIG set up for this. Maybe when I win the lottery. But I'll keep cleaning and shaping.

Final result. (And you can see that "character" in the butt stock!)
Put Humpty Dumpty together. AND IT WORKS! Heaven knows last time that action was cycled!
Still have a complete action stripping and cleaning, and the bore is really almost a literal sewer pipe. But it all looks like it will clean up.
I didn't really clean and blue my work because that weld metal is brittle. I really don't expect it to hold or last too long. It's working now good enough so that I can test the action and do test firing. Later on, I'll get steel plate; use the plasma cutter to take off a small strip; cut the transfer bar about half way up and rivet/weld at the splice.