Well, I have been warned not to, so I probably won't. However, I saw a video online about a gu ywho had a new 638 WITH the internal lock and he actually polished it up enough to make it look like a mirror nickel plate! Didn't think it was eve possible. Though he mentioned things like grinding, maybe sanding be a use he would've had to remove the coated finish but he did it. It's amazing! I'd love to do that, but I'm not that good at it.