State Legality Matrix / Binary Triggers / Massachusetts
Statute-cited, last verified 2026-07-10
No. Prohibited as a rapid-fire trigger activator; the 2024 firearms law names binary triggers. Effective 2024-10-02.
Controlling law: Mass. Gen. Laws ch. 140, §§ 121 & 131M; St. 2024, c. 135
Massachusetts banned bump stocks and trigger cranks in 2018; Chapter 135 of the Acts of 2024 added rapid-fire trigger activator coverage that expressly includes binary triggers and hellfire triggers, effective October 2, 2024 under the emergency preamble. No licensing exception permits possession.
Binary triggers are legal under federal law and are not machine guns under 26 U.S.C. § 5845(b); ATF treats the trigger pull and the trigger release as two separate functions of the trigger, so one round is fired per function. Cargill v. Garland (2024) concerned bump stocks, not binary triggers, and does not change this.
Scope: Binary triggers (Franklin Armory BFSIII and similar): fire one round on trigger pull and one on release. Forced reset triggers are a separate class.
No. Prohibited as a rapid-fire trigger activator; the 2024 firearms law names binary triggers. Effective 2024-10-02. Controlling law: Mass. Gen. Laws ch. 140, §§ 121 & 131M; St. 2024, c. 135.
The controlling law is Mass. Gen. Laws ch. 140, §§ 121 & 131M; St. 2024, c. 135. Prohibited as a rapid-fire trigger activator; the 2024 firearms law names binary triggers.
Massachusetts's rule took effect 2024-10-02. Massachusetts banned bump stocks and trigger cranks in 2018; Chapter 135 of the Acts of 2024 added rapid-fire trigger activator coverage that expressly includes binary triggers and hellfire triggers, effective October 2, 2024 under the emergency preamble. No licensing exception permits possession.
Binary triggers are legal under federal law and are not machine guns under 26 U.S.C. § 5845(b); ATF treats the trigger pull and the trigger release as two separate functions of the trigger, so one round is fired per function. Cargill v. Garland (2024) concerned bump stocks, not binary triggers, and does not change this.