Are Binary Triggers Legal in Montana? State & Federal Laws

Are Binary Triggers Legal in Montana?

Yes, binary triggers are legal to own, purchase, and install in Montana. The state of Montana has no laws specifically prohibiting these devices. They are not classified as machine guns under current federal law or Montana statute, as each round fired requires a separate function of the trigger.

Understanding the Legal Landscape in Montana

Montana's legal framework for firearms is one of the most permissive in the United States, a reflection of its strong cultural heritage of gun ownership and self-reliance. When it comes to firearm accessories like binary triggers, the state's approach is straightforward: if it is not explicitly illegal, and if it is not prohibited by federal law, it is generally considered legal. As of today, there are no sections in the Montana Code Annotated (MCA) that name or ban binary trigger systems.

This legal clarity stems from Montana's deference to federal definitions for regulated firearms. State law primarily concerns itself with the use of firearms in criminal acts, rather than outright bans on specific types of firearms or accessories. Consequently, the legality of a binary trigger in Montana hinges almost entirely on its classification by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). Since the ATF has consistently ruled that these devices do not convert a semi-automatic firearm into a machine gun, they remain legal for Montanans to possess.

It's also important to consider Montana's firearm preemption laws. These statutes generally prevent local jurisdictions like cities or counties from enacting their own gun control ordinances that are stricter than state law. This ensures a uniform legal environment across the state, meaning that a binary trigger that is legal in Billings is also legal in Missoula and Helena, without the need to navigate a confusing patchwork of local rules.

What is a Binary Trigger and How Does It Function?

A binary trigger is a firearm modification that alters the trigger's function to fire one round on the pull of the trigger and a second round on the release of the trigger. This creates a two-shot burst for every complete trigger cycle. This mechanism is distinct from a standard semi-automatic trigger, which fires only one round per pull, regardless of the release. It is also fundamentally different from a fully automatic firearm, or machine gun, which fires continuously as long as the trigger is held down.

The key to its legality lies in that distinction. The ATF's definition of a machine gun, derived from the National Firearms Act (NFA) of 1934 and the Gun Control Act of 1968, centers on whether a firearm can fire more than one shot "by a single function of the trigger." With a binary trigger, the pull and the release are considered two separate functions. Each function results in the firing of only a single projectile. Leading manufacturers like Franklin Armory and Fostech have designed their triggers, such as the BFSIII and Echo series, to adhere strictly to this interpretation.

These triggers typically include a three-position selector: Safe, Semi-Automatic, and Binary. In the semi-automatic mode, the trigger functions exactly like a standard factory trigger. When switched to the binary mode, the two-stage firing sequence is engaged. Users must be aware that if they pull the trigger in binary mode and decide not to fire the second shot on the release, they can switch the selector back to the 'Safe' or 'Semi' position to cancel the release shot. Understanding this functionality is a key part of responsible ownership. Some owners may seek to understand the true gun value of their firearm before or after such a modification.

Federal Law and ATF Rulings

The legal status of binary triggers at the federal level is governed by ATF interpretation. The ATF has issued several opinion letters over the years clarifying its position. These letters consistently state that because a binary trigger fires only one round for the pull function and one round for the release function, it does not meet the legal definition of a machine gun.

This contrasts sharply with the ATF's stance on other rapid-fire devices. For example, bump stocks were reclassified as machine guns via administrative rule-making because they use the firearm's recoil to create a continuous firing cycle from a single, continuous pull of the trigger. Similarly, the ATF has aggressively pursued forced reset triggers (FRTs), classifying them as machine guns because they argue the trigger is forcibly reset by the bolt carrier, enabling a firing rate that mimics automatic fire with a single continuous pull. The legal status of forced reset triggers in Texas and other states remains a contentious issue.

While binary triggers are currently federally legal, owners should understand that the regulatory landscape can change. The ATF has demonstrated its willingness to reinterpret existing statutes, and future administrative or legislative action could potentially alter the classification of these devices. For now, however, based on long-standing ATF rulings, they are treated as a standard firearm part, not a regulated NFA item. This means they can be purchased online or in-store without the extensive paperwork, tax stamp, and waiting periods associated with items like suppressors or short-barreled rifles.

Montana Code Annotated: A Closer Look

To confirm the legality of binary triggers within Montana, one must look at the state's own laws. The relevant section is typically found in the criminal code, defining prohibited weapons. The Montana Code Annotated (MCA) defines a "machine gun" in a manner that closely mirrors the federal definition. It specifies a weapon that shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger.

Because a binary trigger requires two distinct functions—a pull and a release—to fire two shots, it falls outside this definition. There are no other statutes in the MCA that address trigger mechanisms, rate of fire enhancers, or similar accessories. This legislative silence is effectively a green light for ownership. Montana law enforcement agencies are bound by these state-level definitions and cannot treat a binary-trigger-equipped firearm as an illegal machine gun.

This legal stability is a major reason why Montana is a popular state for firearm enthusiasts. The legislature has shown little interest in pursuing the kind of restrictive, feature-based bans seen in other states. For those looking to purchase a firearm suitable for modification, you can browse all gun listings to find a compatible platform. The focus remains on punishing criminal misuse of firearms rather than restricting access to them for law-abiding citizens.

Practical Use and Safety Considerations

While legal, binary triggers come with a steep learning curve and significant safety responsibilities. The primary appeal is for recreational shooting at the range, where they provide a unique and engaging shooting experience. However, the 'one round on release' function requires conscious thought and practice to master safely. A shooter experiencing recoil or surprise might release the trigger unintentionally, causing a second shot they did not plan for. This is known as a 'double tap' and must be controlled through training.

Ammunition consumption is another major consideration. Firing two rounds per cycle can deplete magazines and ammunition stockpiles very quickly, which can become expensive. Shooters should budget accordingly and ensure they are using their firearm at a range that permits rapid fire. Using a binary trigger for hunting is generally discouraged and may be illegal depending on specific Fish, Wildlife & Parks (FWP) regulations regarding magazine capacity or method of take.

Mechanically, some firearms may experience issues when a binary trigger is installed. A common problem is "outrunning the bolt," where the hammer falls on the release shot before the bolt carrier group has fully returned to battery. This can cause a malfunction or, in rare cases, an out-of-battery detonation, which is dangerous. This is more common in firearms with different buffer weights or gas system lengths. Professional installation by a qualified gunsmith is recommended for anyone not completely comfortable with the intricacies of the AR-15 fire control group or a similar platform like the popular Micro Draco.

Ultimately, a binary trigger is a tool that requires a high degree of responsibility. Before installing one, owners should be proficient with the standard operation of their firearm and fully understand the mechanical changes they are making. Reading more about specific firearms, like a guide to the Barrett 50 cal, can provide perspective on the wide range of firearm technologies and their intended uses.