Yes, but like diesel from a gas station it has additives that cause it to stink like hell. Get one drop in the house and you'll have to work like blazes to get the smell out.
There's a couple of videos on You Tube about really badly rusted guns that have been brought back from the dead using electrolysis rust removal combined with other techniques. But first you need to get the guns apart. And that's where the good penetrating oils come in. But then wash them down with a degreaser before the rust removal solutions or using the electrolysis method or the penetrating oils will block the solutions from getting into the rust.