No, binary triggers are not legal in California, and the state treats them as prohibited weapons—even if federal law allows them in other states. Many gun owners misunderstand this distinction because they see binary triggers advertised online or allowed at ranges outside California, and assume they are lawful everywhere. But California has its own classification system for firearm components, and it focuses on how a trigger functions rather than on how a firearm is categorized federally. The moment a trigger system allows a firearm to fire faster than a traditional semiautomatic mechanism, it enters the category of a banned item. This means even buying, owning, importing, or installing a binary trigger in California is enough to break the law, whether or not the firearm is ever used. Understanding this is essential because a single aftermarket part can turn an otherwise legal firearm into contraband under state law.
What Is a Binary Trigger — and Why It Matters
A binary trigger is a device or modification for a semi-automatic firearm that causes the weapon to fire one round when the trigger is pulled, and then a second round when the trigger is released. Technically it doesn’t convert the weapon into a fully automatic firearm because each round still corresponds to a distinct trigger function. Under federal law the device can sometimes pass legal muster — but under California law, the state doesn’t look only at federal rules: it has its own, stricter definitions.
California defines a “multiburst trigger activator” broadly under Penal Code § 16930. That definition includes “any aftermarket trigger or trigger system that, if installed, allows more than one round to be fired with a single depression of the trigger.” That is exactly what a binary trigger does: one “trigger event” (pull + release) results in two rounds fired, which the state treats as a disallowed multiburst trigger system.
What California Law Says
- Possession, sale, manufacture, import, lending, or offering for sale of a multiburst trigger activator is prohibited.Under Penal Code § 32900, doing any of these is a crime.
- A firearm equipped with such a trigger is effectively rendered illegal in the state.
- In June 2025, the state’s Attorney General reaffirmed that “forced reset triggers” and similar devices remain banned under California law — regardless of any federal rulings.
Because binary triggers are classified as prohibited multiburst activators, they are explicitly banned under state law.
What This Means for Gun Owners in California
Americans often hear that binary triggers are “federal-legal,” despite being controversial. But in California, legality doesn’t follow federal permissibility alone. Even if a device passes federal scrutiny, state law can still ban it — and California does exactly that. That means:
- You cannot legally own a binary trigger in California.
- Any firearm equipped with one is unlawful.
- You cannot buy, sell or transfer a binary trigger within the state.
- Possession can lead to criminal prosecution, confiscation, and substantial penalties under California’s weapons laws.
Even if you bought the trigger elsewhere or received it by gift, the state prohibition overrides.
Why California Bans These Devices
California treats multiburst trigger activators — which include binary triggers, forced-reset triggers, bump stocks, trigger cranks, and similar aftermarket parts — as threats to public safety. The law aims to prevent modifications that dramatically increase rate of fire without converting the firearm to a fully automatic weapon (which is already banned). The rationale is that these attachments effectively mimic the firing rate and danger of automatic weapons, undermining the safeguards the state maintains around assault-weapon configuration.
Conclusion
In California, binary triggers are clearly illegal. The state defines them under its multiburst-trigger law, and possession, sale, or use of such devices is prohibited. Even if the device might be legal under federal regulations, California’s stricter laws control within its boundaries. If you own or consider installing a binary trigger on a firearm while living in California, know that doing so violates state law and exposes you to serious legal risk.
