[Slimjim]

First, how do i remove rust around the Peice that seperates the barrels? Still steel wool and mineral spirits?

Also, what do you Call that part that seperates the barrels.

[sm]

Rib separates the barrel

I'd start with "easy" and then work "up" as need to remove rust.

Hose (panty hose) ,gauze from the first aid kit, cheese cloth (kitchen) and Hoppe's No. 9 for starters.
Soft toothbrush works too.

Let is soak, rub, soak and let time work on your side.

Next would be BRASS wool from a hardware/plumbing supply and Light Gun oil.

Slow, easy, and let time assist.

[Slimjim]

I meant to say Four ought steel wool. Not just steel wool.