MGL Chapter 269, Section 10(c):
Possession of a Machine Gun

Section 10(c) of MGL Chapter 269^[1] criminalizes unlawful possession of machine guns and sawed-off shotguns. Chapter 135 of the Acts of 2024^[2] expanded its scope.

Chapter 135 Expansion

Section 115 of Chapter 135 expanded Section 10(c) to additionally cover:

• Bump stocks
• Automatic parts (including Glock switches and auto sears)
• Rapid-fire trigger activators
• Trigger modifiers

The expanded "machine gun" definition in Section 121 includes any firearm modified by automatic conversion to alter or increase its rate of fire to "mimic automatic fire."

Federal vs Massachusetts Law

Federal law and Massachusetts law treat bump stocks differently. Effective May 6, 2026, an ATF final rule^[3] removed the language in 27 CFR 447.11, 478.11 and 479.11 that had classified bump stocks as "machine guns" under federal law. The rescission implemented the Supreme Court's decision in Garland v. Cargill (2024)^[4], which held that a bump stock does not convert a semiautomatic rifle into a machine gun within the meaning of the National Firearms Act. Non-mechanical bump stocks are no longer regulated as machine guns at the federal level after Garland v. Cargill and ATF's 2026 rule, which removed the bump-stock sentences from the three regulatory definitions of "machine gun".

Massachusetts independently prohibits bump stocks at the state level. St. 2017, c. 110 defined them in MGL Chapter 140, Section 121 and counted them as machine guns, and Chapter 135 of the Acts of 2024 now names them directly in Section 10(c). Possession of a bump stock in Massachusetts remains a felony regardless of federal classification. The federal rule amended only federal regulations. Section 10(c) applies to a bump stock as that term is defined in section 121 of chapter 140. The Chapter 135 changes are subject to the November 2026 referendum (see Referendum Status below). If voters repeal Chapter 135, bump stocks stay banned under the 2017 law, which counted them as machine guns.

Penalties

Imprisonment in state prison for life, or for any term of years, subject to the mandatory minimum requirements of paragraph (a): 18 months minimum that cannot be reduced or suspended. Defendant is ineligible for probation, parole, work release, or furlough until 18 months are served.

Exceptions

Machine-gun possession is an offense under Section 10(c) unless the person has permission under Section 131 or the possession is otherwise provided for by law. Section 131 lets a licensing authority issue a machine gun license only to a firearm instructor certified by the municipal police training committee for the sole purpose of firearm instruction to police personnel, or to a bona fide collector of firearms. Section 10(c) provides permission under Section 131 only for a machine gun, not for a sawed-off shotgun, automatic part, bump stock, rapid-fire trigger activator or trigger modifier, and Section 131 states that its machine gun license clauses shall not apply to automatic devices or automatic parts.

Related Provisions

Section 10(d) provides second and subsequent offense enhancement. Section 10(n) provides the loaded weapon enhancement. Section 10G provides enhanced penalties for a person previously convicted of a violent crime or a serious drug offense who violates paragraph (a), (c) or (h) of Section 10. MGL Chapter 265, Section 18B adds a sentence of not less than ten years in the state prison for possessing a machine gun while committing or attempting an offense that may be punished by imprisonment in the state prison.

Referendum Status

The expanded scope covering automatic parts and trigger modifiers is subject to the November 2026 referendum. Bump stocks stay banned either way, under the 2017 law if Chapter 135 is repealed.