Sometimes all you need is that one little piece of evidence. Sometimes you just need that one little ingredient. But, quoting the Stones, "You can't always get what you want".
But sometimes you get what you need. I learned that early on. My grandmother learned to cook in the depression era and could make about anything without some ingredient, be it flour, or eggs or sugar, finding substitutes in her cupboard or in the wild. From her, widowed in her 30's when my Norweigian grandfather was killed in a logging accicdent, my Mom, and the next generation learned to fix their weapons and tools with what was on hand, build a fire from scratch and just generally survive. But they did more than survive, they learned to make and tend to wondrous things, everything from scratch to save money. I've learned to do the same.
quite right, like that paint you loved on the sample at Lowe's that just looks different on your wall. Unless you are part wizard, part gunsmith, the home done all-over cold blue just doesn't impart that beautiful blue black tone you expect from a professional job.
But bluing does get worn, rusted or or gouged with use, and we find yourself soon singing the blues again. But I might advise, for the average person, to use a cold blue just for those small little touch ups. Cold blues only work on normal carbon steels. Some guns, or parts thereon--such as the barrels on my Remington 700 Magnums--are made of stainless steel. They are not blued but darkened with a plating that gives the illusion of bluing. If the metal shows absolutely no sign of darkening, it's probably stainless or some other alloy, which may require a custom touch-up job.
Bluing only works on steel or stainless steel parts for protecting against corrosion. Because it changes the Fe into Fe3O4, it does not work on non-ferrous material. Aluminum and polymer parts are largely unaffected by bluing; no protection against corrosion is provided by bluing processes on them, although uneven staining of the aluminum and polymer parts can be caused by attempts at bluing.
By cold blue, for the new to firearms, I mean the "touch up" bluing that is simply swabbed on. If you're doing it to add color, well, it's better than painting :-) but it offers no rust protection. All blued parts still need to be properly oiled to prevent rust. What it is good for is simply touching up those small areas, those little dings or worn spots that aren't bad enough for a quality reblue but need a bit of color and cover to perk things up. Sort of like my little "Spackle box" of makeup, it provides that little bit of "something" to draw the eye to the finer features.
Like Coca Cola, the quality cold blue manufacturers have highly guarded formulas, each solution with different quality. What you need to concern yourself with is durability, and yes, color. For areas that take a licking, safety buttons, the top levers, bolt handles, you're thinking more for durability. For the rest, a good color match has it's selling points. Some of the newer brands, frankly aren't all that durable and don't pass the steel wool muster.
My favorite - Brownell's Oxpho-Blue. This stuff is tough. You can scrub on it with fine steel wool until the chickens come in to roost and it will not harm the finish one bit. It is also not as picky on grease, oil, and fingerprints when bluing and is much tougher than others. I've used it on an old Mauser that had been used as a can opener I think, to great success.
You can order it from Brownells - World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools or Cabelas carries it as well. Cabela's Official Website - Quality Hunting, Fishing, Camping and Outdoor Gear at competitive prices. It does, however have an appearance that's almost charcoal, more darkest grey than blue/black, and it's a bit more shiny than matte. You may want to try other brands for a color you like better, this is simply my favorite. Some folks online say they've had good luck mixing two or more different brands, alternating between coats. I'd caution anyone from mixing different solutions of different properties. Randomly mixing chemicals can quickly earmark you for the Darwin Awards.
Another reason I like the Brownells. With many blues the littlest bit of oil can mar the end results, but Brownells handles it a bit better than other brands if the gun's not a pristine clean. In fact, the tried and true way I've used it for "touch-ups", is with steel wool, which has a fair amount of oil present in it (to keep the fibers from rusting).
It's easier than you think for a little cosmetic work. Remove the microscopic rust and oil residue by buffing with 000 steel wool. If you don't go wild on it, it won't hard the adjacent bluing. If you've used some of the high-tech lubricants and rust preventatives on the market, especially those containing silicone, you may find it hard to remove from the metal and it may resist the bluing.
Cleaning the metal? A little evaporating solvent such as lacquer thinner or alcohol. Then apply the bluing mixture as per the instructions. Size the application swab to the area being worked on, so you don't get the equivalent of a 38C bra, trying to fit a pair of 32AAs. For tiny little dings, use a toothpick. Q-tips, which you should have on hand for general gun cleaning, are great for the slightly larger little scuffs, and for the large areas, try some cotton balls clamped in a clothespin, or a bit of old clean t-shirt.
Try and do just one pass with the solution, and as evenly as you can, keeping the applicator as saturated with fluid as possible without dripping. The steel getting a good steady bath of it produces the best results. Watch that you don't get the solution on the areas you don't want to blue, that can leave a little "ring" around the area you are working on as areas you didn't want to darken just may. If you see a spot where the solution sort of beads up from a a bit too much oil (like sharp corners), try lightly rubbing these spots with a very sodden Q-tip. Use a new swab for each application, as the residue that can build up degrades the effect you're going for. With the Oxpho blue, what works even better for a deep, streak free finish is, after swabbing it on, use some steel wool, 0000 or finer. Use it like a cloth, no heavy rubbing pressure, it's being blued as well, as it is distributing the bluing solution.
Another suggestion is the Brownells "Oxpho-Blue" Creme Formula which might be a little easier to work with than the liquid. You still need to degrease thoroughly, then try heating the part with a heat gun to just "very warm" applying the bluing with that same type steel wool, and work it in like polishing it and do this several times.
The amount of coats can very, small receptive little parts may just take two or three. In other areas you may need a half dozen or more. If after several coats of cold blue there are spots that just refuse to darken, start over by sanding the area with fine sandpaper. How fine depends on the polish of the adjacent metal; not more than 320- or 400-grit though.
If the process seems to be stalling out, it's time to quit, put everything in a safe place, wash your hands and have a beer. With some blues you'll get to the point where it starts to make it look worse, not better. Remember, you'll not get that same dark richness as you can with a factory blue or a hot blue. It's intended for a little "refreshing" not a complete refinish.
And finally, in my opinion, there are just some guns you don't care if there are a few little tiny dings. Sure you want to prevent rust on those, and you will, with fine care. But covering up every little defect on an older gun is something I would not do for certain weapons. Are not the worn spots from Grandfathers hands, from Dads rifle rack, badges of honor and markers of history? Battle scars honestly won, the marks of hard hands on harder steel, those are history and should not be lightly erased. The worn edges of an officers pistol, carried for twenty years in service and passed on to the family, shows pride in service, not something I would wish to alter.
Around my own eyes are just the faintest beginnings of lines, from laughter mostly. I have my own small dings as well. That little one across my hairline where I decided to see if I could do Mach .82 on my bicycle, the tiny scar above my eye where I wrestled with a tree blind and lost, the few small freckles from hours spent chasing after pheasants in the heart of our nation. These little scuffs, these little marks, are as much a part of me as my breath. And no matter how many years I still have, though I'll wear my sunscreen diligently, I'm not going to resort to any surgical or chemical processes to rid myself of them. When time ages me, I'll wear it with honor.
Some things are just left alone, remaining as they are, with every little thing that makes them particularly unique, each life experience that makes them special - small marks on our memory.
But if you want a little touch up for your sidearm, the cold blue process is worth trying.