That rust at the muzzles may clean up but first that rust must be neutralized ASAP.[/QUOTE]

Is there anything u recommend to treat the rust?

Until you can have the rust properly removed it should be thoroughly soaked with oil and kept well oiled.

That is a fine looking DH that you inherited. And it is in good overall condition. The rust at the tips of the barrels and the checkering on the butt is the only serious issues I can see. Both issues can be fixed.

Checkering may be able to be cleaned up and made correct by adding one or maybe two lines between each of the existing lines, and hen point up. Since the lines now look to be fairly evenly spaced.

very nice gun...i wish i had a lot of relatives with such guns in the closet..this will clean up well useing the advise given by the fellows...charlie

That rust doesn't look all that bad. Rust is between 3 and 6 times thicker than the metal sacrificed in generating it. That, and that it's at the lowest pressure point on the barrels means with a small amount of striking, it probably won't even show up when the barrels are refinished. Rather than straight motor oil, I'd soak it in a dilute mix of motor oil or ATF with kerosene and a dash of acetone. In it's quest to consume the oxygen in the rust, the acetone will pull the oil/ATF in and lift the rust up, making it very easy to scrub away.
That's some pretty neat butt checkering. I'd guess you would measure it in lines per foot rather than lines per inch. It does seem to be done pretty parallel so it might not be that difficult for a guy like Brian to straighten out.

Kind of looks like the checkering on some of the old english muzzle loaders. Some one probable did it with a thread file.

Anyone ever use "Evaporust" on Damascus.? I soaked an old LC Smith in it for a week and it came out looking "New in the white". Might be an alternative to the traditional treatment.

I think that something like Evaporust will remove rust, bluing, patina and near any finish that is on the metal. If it is the product I think it is.

I guess it depends on what he wants to do with this gun. If refinishing the barrels completely is what is intended, then really any rust removal method will work since the metal will have to be re-struck to remove pitting in that area. However, if refinishing is not an option then mild methods of removing the heavier scale will need to be used (oil and mild abrasives), and the pitting can be lived with as part of the story of the gun.

Over all I'd have to say your a lucky man to inherit a gun like this.

If this were mine. I would be on the phone tomorrow talking to Brad Bachelder about sending the gun to him for evaluation of the rust damage & getting his recommendation on what to do about it.

Brads a great guy that knows his stuff & someone I would trust to save this DH -12 by doing the repairs correctly.

"Evaporust" will indeed remove everything on the metal. It will be a clean piece of steel when you take it out. Looks like the last 2" is pretty well FUBAR anyway so I'd give it a try on that part if it was the only choice at reclamation. The best choice is to send it to a restorer. Brian you've done enough of these to know whereof you speak.