Naval Jelly is along the lines of a phosphoric acid rust remover, converts the rusted surface to a phosphate surface. Little will penetrate that. Bluing wont. Clean to bare metal, if you have to sand, polish and grind.
Or, if you just want to make it look old, listen to the others, vinegar was, scrub with steel wool, blue or brown. Let your imagination be your judge. Too bad your imagination doesn't extend to a beatiful deep blue.
I would seriously doubt that there was a cowboy, or anybody else, 140 years ago who said "OH, OH, I want one 'a them old looking finishes, like the gun's a hunnerd years old."
Hell, I just spent 2 months pay, I want the sumbitch to look new!!!
Them of you who want this, god bless you, I wouldn't deprive you of it, but I STILL can't understand it. They WILL eventually get that way.
I know, some of us are too damned old to wait that long, we'll be long gone before they get that way, naturally.
I'd like to ask what one of yunz would say if someone scratched the barrel on your Weatherby. And you'll take a damn near pristine Pietta, which does a pert near perfect job of polishing and bluing, and scrub the finish off to look like an old salt.
Hard to understand.
Cheers,
George