How To Remove Heavy Rust From a Gun?

Rust is the number one enemy to firearms. And it’s easy to see why…guns have metallic parts that are openly exposed to humidity and ambient air which encourage rust.

In worst scenarios, rust can “eat” deep into the metallic parts of your firearm, leading to heavy rust or pitting. This type of rust is more challenging to remove. Not removing it correctly can also make it grow all over again.

In the following post, we’ll share with you some of the most effective methods of removing heavy rust from your gun plus some extra tips on keeping it protected from rust.

Using a coat of oil/lubricant

The easiest method of removing heavy rust from your firearm involves using gun lubricant/oil. For this method, you’ll also need to use your gun cleaning brushes for the best results.

Here’s how to do it:

Spread a liberal amount of oil on the rusty parts of your gun and let it settle for a while to loosen up things.
Now grab your gun cleaning brushes (brass brushes are better than steel ones as they do less damage to your gun finish) and scrub the rusty spots. Make sure you remove as much rust as you can.
Once you’re satisfied with your job, lightly rub the affected surfaces with steel wool pad to remove any remaining traces of rust.
With the rust removed, you’ll mostly like be left with a ruined gun finish. You shouldn’t leave your gun in this condition as the rust will grow again and put your hardware to the trash can.
We advise you to use a light dash of cold blue to help restore finish for the affected areas.

Killing rust with acid

Another effective method of removing heavy rust from your firearm involves using acid.

The idea behind use of acid here is that acids have natural de-oxidizing properties that help easily break down and dissolve rust (iron oxide) for easier removal from your gun surface.

This explains why the chemical rust removers are actually strong acids.

So, which acid should you use for the job?

You can go for a commercial product, or you can use vinegar.

We suggest that you use the latter as it’s more readily available, cheaper, and safer to use.

Removing rust with vinegar is pretty simple, as shown in the following steps:

Soak the rust parts of your firearm in a vinegar solution. Or simply spray the acid on the affected parts (if you have an aerosol can).
Leave the acid for a while to do its job. Depending on the extent of rust and size of affected parts, the acid can take a few hours to overnight to dissolve the rust
When you’re satisfied the vinegar has done its job, wipe off the rust goo off the surface of your gun
Wiping off the slimy substance will help reveal any rusty parts the acid might not have dissolved. (Yes, the acid might not remove all the rust).
In case you discover any unattended parts, just grab your brass brush and do some scrubbing to complete the job.

IMPORTANT: If you use this method, it’s worth noting that the acid will destroy the finish of your firearm, so you’ll need to do some refinishing afterward. This rust removal method is best suited for a gun that’s entirely covered by rust.

Using the Dremel Rotary Tool

If your firearm has been attacked by super-heavy rust and pitting, say after being neglected for years, then the above methods might not get rid of all the rust.

This is where the use of your rotary tool comes into play.

How to use a Dremel rotary tool to remove extensive rust:

(You’ll need to use a small wire wheel set for your rotary tool for this job).

Insert the small wheels on your rotary tool and get it ready for use
Apply a few drops of gun oil on the area with heavy rust or pitting and give it some time to loosen the grip of rust on the gun
Put on your Dremel and run it against the affected area you oiled above. Use paper towels or napkins to wipe the rust. Continue running the rotary tool until you obtain a clean, smooth surface. Be sure to wipe any rust sediments using a clean cloth.

NOTE: without a doubt, using the rotary tool on your gun surface will mean destroying nearly the entire finish of your gun. This means you’ll have to refinish your entire gun afterward. Keep this in mind when using this method.

Stop the rust from returning

Now that you have removed the heavy rust from your firearm, you’ll need to take some measures to ensure it doesn’t return and make you go through the hell of removing it all over again.

The most effective measures include:

Refinish your firearm

Keeping in mind that your gun has been attacked by heavy rust, chances are the finish is badly destroyed, and leaving it that way will give rust an easy time to form again.

If only a small part of your gun finish was affected, you can use cold blue for the refinish job.

If the entire gun needs refinish, however, consider using duracoat finishes as they’re affordable, easy to apply, and don’t require any special tooling.

If you’re skilled in the firearm finish work, then you can use more sophisticated methods like tradition hot salt blue and Parkerizing.

Proper firearm storage

You should also practice proper storage of your firearm. This entails keeping in a cool, dry place where rust can’t easily form.

Avoid keeping your gun in humid areas like garages, attics, and truck trunk.

The Verdict

Neglecting your firearm for years can cause rust to accumulate and eat deeper into the metallic parts, leading to the formation of heavy rust. This kind of rust can be more challenging to remove, especially if you don’t have a clue how to go about it.

In the above guide, we have outlined the 3 main methods you can use to get rid of heavy rust. These induce using oil, dissolving rust with acid, or using Dremel rotary tool.

Using the rotary tool should be your final resort if the first two methods fail.

Once you have removed the rust, remember to add a durable, protective finish on your firearm and store it in cool, dry places to prevent the rust from forming again.