Stainless steel black powder pistol. Previous owner left uncleaned - surface rusted throughout internally, some pitted areas. Gun is functional.

Fully disassembled and most rust inside and out, has been buffed away and cleaned up nicely, but some internal areas can not be reached by the buffer. I can reach them with a Q-Tip, but not really scrub or brush them.

Is naval jelly a good choice for rust on stainless steel? Does it turn the area black or what? And how is it removed once swabbed on?

Or is it the wrong treatment?

Thanks.

I personally wouldn't, it's phosphoric acid and etches the metal, Stainless is corrosion resistant due to passivation it NEEDS to be exposed to air to form a protective oxide layer, etching might mess this up. If you can get to with a q-tip try wrapping some 0000 steel (stainless is best, regular may leave tiny pieces behind that rust) wool around it.

Get some simi chrome polish and try a soft rag first. You won't hurt the stainless it will just polish it out. For the hard to get spots try a dremel with a q tip.

I recommend CorrosionX for any rust problem. I saw it mentioned here on the Forum, tried it, and really like it.
It is good for removing corrosion, and for stopping it to occur.

I bought it for a couple of old blue revolvers that a friend asked me to help with. They were old H&Rs that had gotten pretty rusty. The chemical removed the rust, and didn't attack the blueing that I could see. Used it on a lamp that I had out on my porch that had rusted in spots, and it worked great. Used a little 0000 steel wool, and the rust came right off.

Tom