Are Binary Triggers Legal in Arizona? State & Federal Laws

Are Binary Triggers Legal in Arizona?

Yes, binary triggers are legal in Arizona. They are not defined as machine guns or prohibited devices under Arizona state law. At the federal level, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has consistently affirmed that most common binary triggers do not meet the definition of a machine gun.

Understanding the Binary Trigger Mechanism

Before diving into the legal specifics, it's essential to understand what a binary trigger is and how it functions. A binary trigger is a firearm modification that alters the action of a semi-automatic rifle. Its defining characteristic is its two-stage firing sequence: one round is fired when the trigger is pulled, and a second round is fired when the trigger is released. This functionality is distinct from that of a standard semi-automatic trigger, which only fires a single round upon pulling the trigger, requiring the shooter to release and pull it again for a subsequent shot.

The key to its legal status lies in the concept of a "single function of the trigger." With a binary trigger, the pull and the release are considered two separate functions. The shooter makes a conscious decision for each action, resulting in a single projectile being discharged for each function. This is fundamentally different from a fully automatic weapon, or machine gun, which fires continuously as long as the trigger is held down after a single initial pull. This mechanical distinction is the primary reason why the ATF has, for the most part, not classified these devices as machine guns.

These triggers are popular upgrades for firearms like the AR-15 platform, AK variants, and various pistol-caliber carbines. Owners install them to increase their rate of fire for recreational shooting or competition, providing a unique shooting experience that falls short of true automatic fire. However, proper training is crucial, as the release shot can be unexpected for novice users, potentially leading to unsafe handling if not properly managed.

The Federal Stance: ATF Rulings and Gray Areas

The legality of any firearm accessory in the United States begins at the federal level with the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). The National Firearms Act (NFA) of 1934 defines a "machinegun" as any weapon which 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. For decades, this definition has been the standard against which new technologies are measured.

Major manufacturers of binary triggers, such as Franklin Armory and Fostech, have proactively sought and received determination letters from the ATF for their specific designs. These letters generally state that because the trigger requires two distinct actions (a pull and a release) to fire two rounds, it does not constitute a machine gun under the NFA. The ATF's logic hinges on the fact that ceasing the pull or the release at any point will stop the firing sequence. The shooter remains in control of each individual shot.

However, the regulatory environment is not static. The ATF's recent actions against another type of trigger, the forced reset trigger (FRT), have caused concern within the firearms community. The agency declared that some FRTs are machine guns because the internal mechanism forcibly resets the trigger, allowing for a faster rate of fire that, in their view, constitutes a single trigger function for multiple shots. While the mechanics of forced reset triggers are different from binary triggers, this aggressive reinterpretation of existing law has made some owners wary of future ATF rulings that could potentially reclassify binary triggers. As of now, though, the long-standing approvals for binary designs remain in effect.

Arizona State Law: A Haven for Firearm Owners

Arizona has a well-deserved reputation for being one of the most gun-friendly states in the nation. The state's constitution and statutes reflect a strong belief in the right to keep and bear arms, with minimal restrictions on the types of firearms and accessories that law-abiding citizens can own. When it comes to binary triggers, Arizona law is notably silent, which, in this case, means they are permitted.

The relevant statute to consider is Arizona Revised Statutes (A.R.S.) § 13-3101, which defines "prohibited weapons." This list includes things like explosive devices, automatic firearms not in compliance with federal law, and short-barreled rifles or shotguns. A binary trigger does not meet any of these definitions. Since a binary-equipped firearm is not legally considered an automatic firearm, its possession does not violate this statute. Furthermore, Arizona has a preemption law (A.R.S. § 13-3108) that prevents cities and counties from enacting their own firearms regulations that are more restrictive than state law, ensuring uniform legality across the state.

This permissive legal landscape stands in stark contrast to more restrictive states. For example, the legal framework in other jurisdictions can be far more complex; a look at binary trigger legality in Illinois reveals a completely different set of rules and prohibitions. In Arizona, as long as a firearm accessory is legal at the federal level, it is almost certainly legal at the state level. This straightforward approach simplifies the process for gun owners looking to customize their firearms. The general process for acquiring a firearm, whether from a dealer or a private party, is also very direct, though anyone new to the process should understand the basics of how to buy a gun legally and safely.

Practical Application and Responsible Ownership

For gun owners in Arizona, installing a binary trigger is a relatively simple process. These devices are sold as drop-in trigger groups that can be installed at home with basic tools by anyone with mechanical aptitude. They are widely available online and in local gun stores throughout the state. Many shooters install them in popular platforms like AR-15s, AR-10s, and pistol-caliber carbines. Firearms like the SIG Sauer MPX is a popular host for these types of upgrades due to its robust design and low recoil.

While legal, responsible ownership of a firearm equipped with a binary trigger is paramount. The increased rate of fire requires more practice to control effectively. Shooters must be intimately familiar with the trigger's function to avoid unintended discharges, especially under stress. A common issue called "hammer follow," where the hammer falls without striking the firing pin because the trigger is manipulated faster than the bolt carrier can cycle, can occur and requires user training to prevent. It is also important to consider the increased ammunition consumption and the rules of the specific shooting range you attend, as some ranges may have policies restricting their use.

When it comes time to part with a firearm, owners may wonder about the implications of selling a gun with a binary trigger already installed. In Arizona, private firearm sales are legal and do not require a background check. The process is straightforward, but sellers should always prioritize safety and ensure they are complying with all applicable laws. Following a clear guide on how to sell a gun can help ensure a smooth and legal transaction, whether the firearm has aftermarket modifications or not. Prospective buyers can find a wide variety of firearms, including those with custom parts, when they browse all gun listings available from sellers across the country.