Firearms
What Is Gun Bluing & How to Do It

What Is Gun Bluing & How to Do It

What Is Gun Bluing & How to Do It

You probably loved the sleek metallic beauty and well-oiled performance of your gun when you first bought it. If you want to keep feeling that way about your firearm, you need to take proper care of it. Otherwise, the firearm will develop rust. Besides ruining the aesthetics, rust increases the likelihood of a gun jamming or even exploding when fired.

What’s the best way to keep your gun looking and working like brand new? We recommend gun bluing and cleaning. If you’ve never heard of gun bluing, you are in luck because we are about to explain what it is and how to blue a gun to maintain its look and performance.

What Is Gun Bluing?

For centuries, gun manufacturers and owners have blued firearms to improve their appearance and corrosion resistance. The bluing process involves treating a gun with a solution that turns red iron oxide or rust (Fe2O3) into black iron oxide (Fe3O4). Bluing also creates a thin protective layer that protects guns from damaging pollutants.

The process turns a gun barrel blue because black iron oxide has a blue-black color. Besides the body and barrel of your gun, you can blue its components, such as the slide, magazine, frame, and even small components. However, some experts advise against bluing gun springs.

There are several methods for bluing gun parts, and the most popular ones are cold and hot-bluing. We will explain both methods later in this article.

What Is Gun Blue Made of?

The exact contents of a gun blue solution will depend on the product you buy. For instance, some cold blue solutions contain a selenium dioxide-based compound that will give your gun a blackish or dark greyish hue. You can also find cold-bluing solutions that contain hydrochloric and nitric acids.

Hot blue solutions may contain mercury bichloride and an alkali salt mixture of sodium hydroxide and potassium nitrite or sodium nitrate. These compounds work together to eliminate red rust and reduce friction in firearms.

How Long Does Gun Blue Last?

Bluing gun parts can preserve the appearance and performance of your gun. However, since bluing does not last forever, you will need to reblue your gun occasionally. High-quality bluing can last for decades, especially if humidity is low in your area and you keep your weapon dry and clean.

Does Gun Bluing Prevent Rust?

Before and After

Photo Credit: WTAC

Gun bluing does a better job fixing rust than preventing it. For superior rust protection, you should oil and clean your gun frequently.

Some experts recommend doing light cleaning after firing your weapon. You can do a deeper cleaning once a year if you rarely fire your gun or twice a year if you frequently fire your weapon. A deep cleaning will typically require disassembling your gun to clean each component.

If you regularly visit the shooting range with your gun, you should oil it at least once every two weeks to prevent rust. Gun owners that rarely fire their weapons should oil guns at least once a month. Regular oiling is especially crucial if you live in a humid area that promotes rust.

Hot-Bluing vs. Cold-Bluing

The correct answer to how to blue a gun depends on who you ask. That’s because several gun bluing techniques are available, including rust and fire bluing. However, among all the techniques, hot-bluing and cold-bluing are the most popular because you can do them at home.

Both methods improve a gun’s aesthetics, corrosion resistance, and life span, but hot-bluing delivers longer-lasting results. Keep reading for more on the differences between cold and hot-bluing.

Hot-Bluing a Gun

Gun bluing used to take days and require special equipment. Thanks to hot-bluing, you can now give your gun a beautiful blue-black finish within a couple of hours at home.

The hot-bluing process requires cleaning your gun’s parts before dipping them in a heated bluing solution. You will then rinse off the bluing solution and clean the gun. However, note that hot-bluing is best for steel and stainless steel guns.

Cold-Bluing a Gun

Unlike hot-bluing, you do not have to heat a solution to cold blue a gun. However, cold-bluing isn’t as durable as hot-bluing because friction against fabrics or other materials can rub it off. It also does not provide as much corrosion resistance as hot bluing.

Before cold-bluing your gun, you must clean, polish, degrease, and dry it. You will then apply the cold-bluing solution to your gun parts. After 12 hours, you can scrub the rust off the gun and reapply your bluing solution. You will repeat the cleaning and bluing process every 12 hours until you restore your gun to your satisfaction.

Since cold-bluing is not as durable as hot-bluing, we do not recommend it for restoring your whole weapon. Instead, hot blue your whole weapon and use cold-bluing to touch up scratches and small rust patches that may appear over time.

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How to Blue a Gun

Would you like to blue your gun? If so, below is a step-by-step guide on how to reblue a gun with the hot-bluing method:

1. Polish Your Gun Barrel

When you are ready to reblue your gun, the first thing to do is unload and disassemble your firearm. Then, polish the barrel and any other surfaces that have rust. You can also use this opportunity to scrub scratches or pits off the gun’s body.

We recommend using either 0000 steel wool or 600-grit sandpaper for the polishing. Grade 0000 steel wire wool can polish metal and dig out rust without damaging or marking the surface.

2. Cut a Good Length of Soft Wire for Your Gun Barrel

To dip your gun parts in a hot bluing solution, you will need some soft wire – about 20 inches long. You will tie one end of the wire to a gun part and hold the other end to immerse and suspend the gun part in the bluing solution.

3. Thread the Wire Through the Barrel

Insert the soft wire inside the gun barrel and bend the end into a hook when it comes out at the other end of the barrel. Doing this will prevent the barrel from sliding off the wire. You will need separate wires for the frame and slide. You can place smaller gun parts in a stainless steel basket, which you will lower into the bluing solution. Just remember not to blue your gun springs.

4. Submerge the Gun in Cleaning Solution

Wear protective gloves and submerge your gun parts in a cleaning solution for at least 15 minutes. Experts recommend using naphtha – a liquid hydrocarbon mixture. Alternatively, you could use sodium triphosphate or a product like Ballistol, FrogLube, or Hoppes Elite. Towards the end of your 15-minute soak, scrub the gun parts to remove stubborn bits of dirt, oil, or grease.

5. Rinse the Gun with Cold Water

After soaking your gun parts in the cleaning solution, take them out and wash off the cleaning solution with a mild dishwashing detergent. Then, thoroughly rinse off the detergent with water. Using cold water to remove all traces of detergent will take longer, while hot water will do the job faster and more thoroughly.

6. Heat the Bluing Liquid

Dry your rinsed gun components and set them aside. Pour your hot bluing solution into a pot or metal container that’s large enough to hold your gun. Stir the contents of the pot until there are no undissolved lumps. Place the pot over the stove and boil it until it reaches at least 275 degrees Fahrenheit or the temperature specified in the product instructions.

7. Dip the Gun Parts into the Solution

Hold each gun part by the attached soft wire and dip it into the bluing solution. If your pot isn’t large enough to contain all the gun parts at once, we recommend dipping one gun component at a time to avoid overcrowding within the container. Also, you must fully submerge each component to ensure that every part gets an even coating of the bluing solution.

As for your gun parts in a metal basket, submerge them and stir the basket to give each component an even bluing solution coating. Every component should stay in the hot bluing solution for 15 to 30 minutes. You can remove a gun part from the bluing solution when you are happy with its new blue-black coat.

8. Rinse the Gun Again in Cold Water

Wash off each gun part under cold water to remove any excess bluing solution clinging to the body.

9. Dip the Gun into Boiling Water

Transfer the freshly rinsed parts into a pot of clean boiling water. Submerge each component in the water for at least ten minutes to remove any bluing solution residue that may interfere with the gun’s performance.

Ornate parts may need to sit in hot water for up to 30 minutes to allow the water to penetrate and clean the crevices. If your gun has soldered parts, you may need to use a cotton swab to blue and clean those portions separately.

10. Soak the Gun in Oil

Take the gun parts out of the hot water and wipe them dry before submerging them in water-displacing oil. Let the parts soak in the oil for about an hour, then wipe them clean and assemble your gun. The oil will amplify the corrosion resistance of the new blue-black finish and protect your gun from damage caused by sweat, body oils, and other contaminants.

Blue Your Gun at Home!

Note that bluing is not suitable for every gun. For instance, hot or cold-bluing vintage guns can negatively affect the firearm’s value. Also, hot-bluing can damage guns with silver soldered components.

If you have a steel gun, restore your firearm with the simple gun bluing steps we provided above. It costs less time and money than paying a gunsmith to do it for you. Even better, you can use the same bluing technique to restore metal gun accessories, such as your silencer.

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