Are Binary Triggers Legal in Colorado? State Laws & ATF…

Are Binary Triggers Legal in Colorado?

Yes, binary triggers are currently legal to own and install in Colorado. State law bans 'rapid-fire trigger activators,' but binary triggers do not meet this specific legal definition because they require a separate function of the trigger for each shot (one pull, one release). They remain subject to all federal regulations.

Decoding Colorado's 'Rapid-Fire Trigger Activator' Statute

The core of the legal question in Colorado revolves around Colorado Revised Statute § 18-12-111. This law prohibits the sale, transfer, and possession of 'rapid-fire trigger activators.' The statute defines this term as any device, including a removable manual or power-driven trigger-activating device, that is designed to increase the rate of fire of a semi-automatic firearm. Crucially, the law specifies devices that allow the firearm to discharge 'two or more shots in a single continuous pull of the trigger.' This language is precise and is the reason binary triggers are generally considered legal in the state.

A binary trigger does not fire two or more shots in a single, continuous pull. Its function is distinct: one round fires on the pull of the trigger, and a second round fires upon the release of the trigger. Each action, the pull and the release, is a separate function resulting in a single shot. Therefore, it doesn't meet the 'single continuous pull' language laid out in the Colorado statute. This is a critical distinction that separates them from devices like bump stocks or other activators that the law was originally designed to target.

The Mechanical Function of a Binary Trigger

To appreciate the legal distinction, it's essential to understand the mechanics. A standard semi-automatic trigger fires one round when the trigger is pulled and then resets as the bolt cycles. The trigger must be fully released before it can be pulled again to fire another round. A binary trigger, such as the popular Franklin Armory BFSIII, alters this process. It features a third selector position, often marked with a 'B' or similar symbol.

In this binary mode, the trigger mechanism operates in two distinct stages. The first stage is the pull, which releases the hammer to fire a round, just like a standard trigger. The second stage occurs upon the release of the trigger. As the trigger moves forward to its reset position, it releases the hammer a second time, firing another round. The shooter must consciously perform two separate actions (pull and release) to fire two shots. This two-stage mechanical process is fundamentally different from a machine gun, which fires continuously as long as the trigger is held down. Many modern firearms, like the versatile SIG Sauer MPX platform, are popular hosts for these trigger systems.

Federal ATF Stance vs. Colorado State Law

On the federal level, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has, as of now, consistently maintained that most common binary triggers do not classify as machine guns. The National Firearms Act (NFA) defines a machine gun as a weapon that shoots, or can be readily restored to shoot, 'automatically more than one shot, without manual reloading, by a single function of the trigger.' Since a binary trigger requires two functions—a pull and a release—for two shots, the ATF has not classified them as machine guns.

This federal position provides a baseline, but state laws can be more restrictive. In Colorado's case, the state law focuses on that 'single continuous pull' language, which aligns well enough with the federal 'single function' definition. This means that for now, binary triggers are not prohibited at either the federal or state level in Colorado. Anyone looking to purchase a firearm to modify should still follow the standard legal process for acquisition, as detailed in our guide on how to buy a gun legally and safely.

Legal Precedents and Enforcement Ambiguity

While the text of C.R.S. § 18-12-111 seems clear, there is limited case law in Colorado specifically challenging the legality of binary triggers. This lack of judicial interpretation means that the legal status, while strong based on a plain reading of the statute, has not been formally battle-tested in a Colorado courtroom. This can create a degree of ambiguity for owners. Law enforcement officers may not be familiar with the nuanced mechanics of a binary trigger versus a truly illegal modification.

An officer might mistakenly believe the device is a prohibited 'rapid-fire trigger activator' during a stop or inspection. While a correct understanding of the law should ultimately clear the owner of wrongdoing, it could lead to temporary confiscation of the firearm and potential legal costs to resolve the situation. Owners should be prepared to calmly explain the 'pull and release' function and understand that the burden of proof may fall on them in a practical sense, even if the law is on their side. The situation is much clearer for forced reset triggers, which are viewed very differently by regulators, a topic explored in depth for other jurisdictions like the legal status of FRTs in Texas.

Practical Ownership Considerations in Colorado

Beyond the letter of the law, there are practical considerations for owning a firearm with a binary trigger in Colorado. First, many public and private shooting ranges have their own rules that may prohibit the use of any trigger modification that increases the rate of fire. Always check the range rules before you go. The rapid succession of shots can be a safety concern for range officers, regardless of the device's legality.

Second, consider the firearm's purpose. For home defense, a binary trigger can be a liability due to the risk of an unintended second shot under stress. For competition or recreational shooting, they can be a fun and effective tool. When it comes to firearm modifications, it's also wise to consider the impact on the firearm's resale value. Keeping track of the true value of your firearm and its components is important for any owner. Ultimately, responsible ownership means understanding both the law and the practical application of your equipment. You can browse all gun listings to see how various firearms are configured and valued by sellers in the market.

Binary Triggers vs. Other Rapid-Fire Mechanisms

It's helpful to compare binary triggers to other devices to understand why their legal status is different. Bump stocks, now federally prohibited, used the firearm's recoil to 'bump' the trigger against the shooter's finger, simulating automatic fire. Forced Reset Triggers (FRTs) use the energy from the bolt carrier to force the trigger to reset, allowing for extremely rapid follow-up shots with a single, continuous pull. The ATF has classified FRTs as machine guns.

Both of these devices fall more squarely into the category of what lawmakers intended to ban. A binary trigger, however, maintains a direct 1-to-1 relationship between a shooter's action and a round being fired. You pull, it fires. You release, it fires. There is no external force or continuous cycling involved. This mechanical distinction is everything in the eyes of the law. While a high rate of fire is achievable, it's entirely dependent on the user's skill, unlike a fully automatic weapon such as the military's M2 version of the Barrett .50 caliber rifle.