When I clean the barrel of my rifle, I often forget to place a cloth at the muzzle end while spraying gun oil inside. As a result, excess oil drips onto the floor. It never occurred to me to use a device designed to trap solvents, nor had I seen one in use until recently. I must say, I was quite impressed!
Solvent traps are specifically crafted to aid in the gun cleaning process by preventing excessive oils or solvents from dripping out of the barrel and creating a mess. The solvent trap, mounted at the muzzle, enables the collection or proper disposal of reusable oil or solvent, maintaining cleanliness.
At first glance, modern solvent traps may be mistaken for suppressors. However, they serve completely different purposes. Let's delve into the exact definition of a solvent trap and explore its intended use. You might discover that a solvent trap is the firearm accessory you never knew you needed.

What Is A Solvent Trap?
A solvent trap refers to an enclosed tube-shaped attachment that screws onto the muzzle of your firearm, designed specifically to capture solvents utilized during the cleaning of the gun's barrel. This cylindrical "can" creates a sealed environment, effectively preventing oils and solvents from dripping onto the floor or your working surface when they exit the barrel.
The primary purpose of solvent traps is to catch and inhibit the dripping of oil and solvent onto various surfaces in your workspace. Typically, gun oils and solvents are packaged in aerosol cans, which are convenient for application as the pressurized expulsion ensures thorough coating of gun parts.
However, a drawback of using pressurized cans is that a significant portion of the oil or solvent often escapes through the opposite end of the barrel. This becomes particularly noticeable when cleaning firearms with shorter barrels, such as pistols. As a result, the oil ends up on the floor, furniture, or any other surface it happens to land on. The solvent trap is ingeniously designed to capture the overspray and minimize the release of airborne vapors.
The solvent trap can be easily disassembled, allowing safe access for the disposal of solvents and grime accumulated during the cleaning process.
Are Solvent Traps Legal?

The appearance of most contemporary solvent traps closely resembles that of suppressors. The only notable distinctions are the absence of an exit hole in the end cap and the design of the internal baffles. Numerous countries mandate the licensing or registration of suppressors, commonly known as silencers, with the local firearm authorities.
However, it's important to note that solvent traps are entirely legal in the United States since they do not function as suppressors, despite their similar appearance. Solvent traps serve the purpose of collecting excess solvents used during the harmless and safe gun cleaning process. Silencers, on the other hand, are designed to reduce the noise generated by gunfire.
Adapters or thread protectors enable the attachment of a solvent trap to the muzzle or barrel of a firearm in the same manner as a suppressor would be attached. Solvent traps have threading on one end of the tube, while the other end remains sealed. These threaded sizes are compatible with the most commonly used barrel thread sizes.
Materials Used in Solvent Traps
Commercially manufactured solvent traps are commonly constructed from aluminum, carbon steel, stainless steel, or titanium. Another option favored by DIY enthusiasts involves utilizing oil filters designed for cars. These filters are typically made of tin and have threading that allows them to be attached to the end of a gun's barrel using a compatible adaptor.
While oil filter-based "solvent traps" can function adequately, they may not be visually appealing if you aim to impress your friends. Personally, I prefer the purpose-built, commercially available versions, as they are more streamlined and compact.
It's worth noting that certain solvents can be corrosive to certain metals if left standing for prolonged periods. Therefore, solvent traps should not be made from brass or copper, as solvents remove these materials from firearm barrels. Carbon steel, stainless steel, and titanium are ideal choices for solvent trap construction since they do not react with ammonia, which is a common active ingredient in solvents.
Among these materials, stainless steel and titanium are particularly recommended due to their strength and durability. However, it's important to keep in mind that larger solvent traps tend to be heavier. For those seeking a lightweight and cost-effective option, aluminum is the preferred choice.
Ultimately, your budget will play a significant role in determining the solvent trap you choose to purchase, as stainless steel and titanium options can be relatively expensive. Related Articles: Which material should you choose for Solvent Trap?
How Do Solvent Traps Work?
Solvent traps work by attaching to the threaded end of a gun's barrel, trapping solvents and oils used during the cleaning process. The trap is a metal tube with a closed end, either permanently sealed or with a threaded cap. The threaded end of the trap attaches to the gun's barrel like a suppressor or muzzle brake.
Inside the trap, cup-shaped baffles collect the solvents and oils, preventing them from running back into the barrel when the muzzle is elevated. Some traps are modular and allow you to adjust the number of cups to suit your needs. Some models even have specially designed end caps that trap the solvents for later disposal or reuse.
Once the gun cleaning process is complete, the trap is removed from the barrel and dismantled by unscrewing the removable end. This allows the solvents to be disposed of safely, and the internal components of the trap can be cleaned. Solvent traps are a useful tool for gun enthusiasts to collect excess solvents and oils while cleaning their firearms. Related Articles: How a Suppressor Works

Distinguishing Between Fuel Filters and Solvent Traps
International online shopping platforms often offer various types of inexpensive "solvent traps" that are commonly marketed as "fiel filters" (fuel filters) while mentioning their potential use as solvent traps. These filters are readily available and priced under forty dollars, in stark contrast to genuine solvent traps, which can cost ten times more or even higher.
The primary distinction between these predominantly Chinese-made solvent traps and authentic products lies in the pre-drilled internal baffle configuration, with only the end cap being closed and threaded for easy removal. The internal baffles are typically crafted from a single tube, often intricately machined, resembling the internals of a suppressor rather than a dedicated solvent trap.
Authentic solvent trap baffles, on the other hand, are not pre-drilled. In the United States, it is unlawful to purchase or possess these "fiel filters" without first completing the Form 1 application and obtaining approval from the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF).
Some firearm owners may be tempted to purchase these cheap filters online with the intention of converting them into suppressors. They may believe that only drilling the end cap is necessary to allow the bullet to exit. In fact, certain filters even have a recessed marking indicating where to drill the end cap.
Through research, we have determined that obtaining approval for owning a suppressor or silencer through the ATF can take up to a year. In comparison, the Form 1 approval process takes approximately a month, which may entice individuals to pursue the Form 1 route and purchase a convertible filter online.
However, we strongly recommend waiting for the full year and acquiring a proper, purpose-built silencer to ensure satisfaction and compliance with the law. The online products from overseas sources lack the solid construction and quality materials necessary for reliable performance. If you are tempted to convert a filter into a silencer, be aware that it should only be used with relatively low-powered calibers or subsonic 9mm rounds. Using it with a 5.56 caliber round will cause damage to the "filter silencer."
It's important to note that countries outside the United States are not bound by American laws. Consequently, unscrupulous retailers may readily accept orders for "fiel filters" and ship them to customers. However, simply placing an order for such products constitutes the purchase of an illegal item. We strongly advise against engaging in such transactions. Instead, opt to buy locally from reputable distributors to ensure compliance with local regulations and remain on the right side of the law. Related articles: What you need to do to register the solvent trap with ATF
The Difference Between C and D Type Solvent Traps
The differentiation between C and D type solvent traps pertains to their diameter. Solvent traps come in various sizes and configurations to accommodate different gun calibers. The length of solvent traps can range from as short as two inches to as long as ten inches, with the latter being considered large.
For larger caliber firearms with bigger barrel diameters, correspondingly larger diameter solvent traps are required. Typically, C-type solvent traps have a maximum thread protector dimension of ½ x 28, which is the standard thread size for calibers such as .22LR, 5.56mm, and 9mm in the United States. On the other hand, D-type solvent traps can accommodate up to 5/8 x 24 thread protectors or adapters, which are suitable for larger calibers.
Thread protectors or adapters, also known by those terms, come in various thread sizes when opting for a high-quality product. Since gun barrel diameters increase with the caliber, it is crucial to ensure that your solvent trap has a sufficient diameter for your firearm. Additionally, aftermarket adapters are available, allowing you to use the same solvent trap on barrels of different sizes.
When purchasing additional adapters, it is essential to specify whether you need a C or D type and ensure that you choose the same brand as your solvent trap to ensure compatibility between the threads connecting the adapter and the solvent trap tube.
Are Solvent Traps Useable On All Weapons?
Most solvent traps require the gun's barrel to have threading in order to attach the solvent trap. Thankfully, companies like "Lethal Eye" and others offer threaded adaptors that can be slipped over the gun's barrel. These adaptors are secured in place using grub screws that press against the barrel when tightened.
However, there is a limitation when using slip-on adaptors, as you need to find the appropriate size adaptor for your specific gun's barrel diameter. Alternatively, a skilled gunsmith can create a custom slip-on adaptor that suits your needs.
In the case of pistols, they typically don't have threaded barrels in their standard configuration. Additionally, the barrel doesn't extend far enough out of the front of the slide to allow for threading or the use of a slip-on adaptor. The only practical option to attach a solvent trap to a pistol is to replace the barrel with a longer one that is threaded.
Revolver barrels also present a challenge for attaching solvent traps since they are usually not threaded. However, it is possible to have the exterior of the barrel threaded. Ideally, finding a slip-on adaptor that precisely fits the diameter of your revolver's barrel would be the best solution.
One consideration with revolvers is that modifying or repositioning the front sight may be necessary to create space for the threads. This modification would likely require the expertise of a gunsmith.
Shotgun barrels, due to their large diameter, are not suitable for solvent traps. Over-under and side-by-side barrel shotguns cannot accommodate solvent traps.
In conclusion
In conclusion, solvent traps serve as valuable tools for preventing spills and containing solvents and oils during gun cleaning. These cylindrical devices, resembling silencers, are attached to the muzzle end of the gun's barrel.
By capturing the expelled oils and solvents, solvent traps provide a safe and convenient way to dispose of or reuse them in a responsible manner.