Does Massachusetts Have an Assault Weapons Ban?

Massachusetts General Laws chapter 140, section 121 now defines an assault-style firearm through separate two-feature tests for semiautomatic rifles, pistols, and shotguns, an assault-style-firearm roster, named models, and a copy-or-duplicate test based on internal components or interchangeable receivers.

Section 131M's retained-possession provision is tied to lawful Massachusetts possession on August 1, 2024 by a license holder and requires registration under section 121B and serialization under section 121C. The definition also excludes specified manual-action, permanently inoperable, antique, listed sporting, and limited shotgun categories.

There has been no federal assault weapons ban since the 1994 ban expired in 2004; no feature restrictions apply federally to semi-automatic rifles or pistols. The 2023 ATF pistol-brace rule was vacated nationwide and is not enforced, but federal SBR classification for a brace-equipped firearm still turns on whether the specific weapon is designed and intended to be fired from the shoulder. Cargill v. Garland (2024) made bump stocks federally legal. Feature bans are entirely a matter of state law.

Federal baseline verified 2026-07-31. Scope: State laws restricting semi-automatic rifles, pistols, and shotguns by configuration features: threaded barrels, pistol grips, folding or telescoping stocks, flash suppressors, forward grips, and similar. Magazine capacity limits are tracked as a separate class.