Removing Rust from Your Gun

Rust. Every firearms owner should cringe when they hear the word. It can devalue your most prized weapon without much warning. Thankfully, it is easy to prevent if you keep your firearm properly cleaned and oiled. Instead of talking about how to prevent it, I am going to discuss how to remove rust that may have already started.

When I was asked to do this article, I was excited to thumb through my library to find some excellent sources and have big names to back up the information. That wasn’t the case. Almost every book that I referenced had a section about rust removal, but all of them focused on completely refinishing the firearm. I wanted to approach this in a different way as most people don’t have the means or desire to reblue their firearm. This will give you a cost effective way to remove rust at home and prevent it from causing anymore damage to your firearm.

I could list off a bunch of magical chemicals and solutions that are advertised to remove rust and send you on your way. It may work and it may not. However, removing rust from firearms is a completely different animal than removing it from the wrench in your garage and if you use the same process you could ruin the value of your gun. Bluing is a form of rust. Therefore, you must remove rust without removing rust. Makes sense right? 

To properly and professionally get rid of rust from a firearm you need to have a good understanding of what rust is. Rust is the corrosion and oxidation of iron or steel, and is caused by being exposed to moisture and oxygen for a period of time. Here in Montana, it may take weeks for rust to form on a hunting rifle that was carried in the rain. In some of the more humid areas like the Southeast, that same exposure can cause rust to form in less than a day. 

What is Gun Rust?

Rust’s chemical makeup is Fe₂O₃ while gun bluing’s chemical make up is Fe₃O_4. Simply put, gun bluing is a black oxide coating of iron. This coating is not very corrosion resistant until it is paired with an oil. That’s a lengthy way of saying that commercial rust removers may remove your bluing as well, turning your small rust removal project into a full refinish that more than likely needs to be done by a gunsmith. Let's leave the chemicals out on this one.

For this discussion we are going to deal with surface rust, deeply pitted metal is a completely different animal and requires a lot more of a process than what most individuals can do at home. Deep pitting forms when the surface rust is ignored for a long period of time.

There are numerous techniques that can be used to remove surface rust from your firearm, and I’m going to walk you through a couple of the ones that I have found to work consistently. When using any of these techniques, it is important to always consider the materials that the tools you are using are made of. Specifically, their hardness and whether they will scratch the steel or finish on your gun. Copper brushes, brass picks, bronze wool, and my favorite, a penny, are all good options here.

How To Remove the Rust

To start, check and make sure your chamber is clear and disassemble your firearm to a point where you can easily get at the rust you plan on removing. If it is toward the end of your barrel or somewhere easy to reach, disassembly may not be necessary. Always use correct fitting screwdrivers and reference a disassembly guide to avoid marring up your screw heads and sending springs across the room.

Once disassembled, hold your workpiece in a secure way; a padded vise is optimal but not necessary. We’re going to use a penny first, as this technique works best for that thick looking rust that is still on the surface. Keep in mind that this won’t make your firearm look completely new, but will remove the rust and prevent it from continuing to grow. 

3 Methods of Rust Removal

Extra care must be taken if you notice rust forming in your bore, but the principles are the same. Apply your favorite solvent to a patch and run it through the bore. Let it sit for about 15 minutes and then run your cleaning brush through the bore repeatedly. Run a few dry patches through and repeat until you have the results you want. This may take longer than the same treatment on the outside of your firearm but is worth the effort in preventing it from getting worse and potentially affecting your accuracy.

These are three ways that I regularly use to remove rust on firearms that come across my bench. There are absolutely other methods of doing this, however these are some of the most effective methods out there. None  of these methods take much time and can be worked into your annual cleaning cycles of your working guns to have them operate smoothly for years to come.

Written by Kurtis Martonik