Maryland Senate Bill 334
Senate Bill 334, signed by Gov. Wes Moore on May 26, 2026, creates a new category called a “machine gun convertible pistol” and, beginning January 1, 2027, makes it a crime to manufacture, sell, offer for sale, purchase, receive, or transfer one in Maryland.
The statute does not require that anyone actually install an illegal device.
It targets pistols whose internal design, specifically a cruciform trigger bar could, in theory, accept a separate, already-banned part known as a pistol converter, Glock switch, or auto sear. An unmodified Glock or Glock-pattern pistol fires one round per trigger pull. The law treats that legal firearm as the problem.
What SB 334 Actually Prohibits
The operative language is straightforward. After January 1, 2027, Maryland Criminal Law §4-305.2 forbids commerce in any “semiautomatic pistol with a cruciform trigger bar that can be readily converted by hand or by using common household tools into a machine gun by the installation or attachment of a pistol converter as a replacement for the slide’s backplate.”
A cruciform trigger bar is a cross-shaped internal component that has been part of the Glock design since the G17 appeared in 1982. It is not an aftermarket accessory. Hammer-fired pistols and certain striker-fired designs without that feature are excluded. Possession of a pistol already lawfully owned is not criminalized, and limited transfers to immediate family members remain allowed. Law enforcement and specified military uses are carved out. Violations are a misdemeanor punishable by up to three years in prison and a $5,000 fine.
The Maryland State Police must publish a list of prohibited models. Until that list appears, the statutory definition controls. In practice, coverage is widely expected to include the bulk of the Glock lineup and many Glock-pattern pistols from other makers. The act itself takes effect October 1, 2026; the sales-and-transfer ban begins January 1, 2027. As of mid-September 2026 the law remains in effect and is being challenged in federal court.
The Conversion Device Was Already a Crime
The political framing of SB 334 is the “Stop DIY Machine Guns Act.” That framing treats the legal pistol as a precursor to an illegal machine gun. The conversion itself has long been illegal under both federal and Maryland law.
Under the National Firearms Act, 26 U.S.C. §5845(b), a “machinegun” includes any weapon that shoots automatically more than one shot by a single function of the trigger, and “any part designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machinegun.” A Glock switch, auto sear, or pistol converter is itself classified as a machinegun. Possession, manufacture, or transfer of an unregistered post-1986 machinegun is a federal felony under 18 U.S.C. §922(o), carrying up to 10 years in prison and a $250,000 fine. The device does not have to be installed. Possessing the part is the crime.
Maryland already banned the same category of devices. Since 2018, Criminal Law § 4-305.1 has prohibited transporting, manufacturing, possessing, selling, transferring, purchasing, or receiving a “rapid fire activator.” That definition includes bump stocks, trigger cranks, binary triggers, burst triggers, and switch/auto-sears. SB 334 simply added “pistol converter” to the existing list. Conversion devices were already unlawful in Maryland; that prohibition did not change.
In other words, the person who actually converts a pistol into an unregistered machine gun was already facing serious federal and state charges. The new statute does not add a day to that sentence. It instead restricts the unconverted handgun that a law-abiding buyer would purchase at a licensed dealer.
Restricting the Legal Gun, Not the Illegal Act
An unmodified Glock is a semiautomatic pistol. It is among the most commonly owned handguns in the United States and is widely used by civilians, police departments, and competitive shooters. The conversion device is a small aftermarket part, often 3D-printed, that replaces the slide’s backplate and interferes with the trigger mechanism so the pistol fires automatically. That part is the crime. The factory pistol is not.
SB 334 inverts that distinction. It defines the legal firearm by its theoretical compatibility with an illegal part and then bans future commerce in the firearm. Supporters argue manufacturers should redesign pistols so conversion is harder. Critics note that the design in question has been on the market for more than four decades, that millions of such pistols are already in circulation, and that criminals who obtain illegal switches are not waiting for a lawful retail purchase in Maryland.
The law does not require proof that any particular pistol has been converted. It does not require that a converter even exist in the same household. The restriction attaches to the stock gun. Current owners may keep what they have, but they generally cannot sell or transfer it except to immediate family. That freeze on the secondary market reduces the value of property already lawfully acquired and limits the ability of new Maryland residents or first-time buyers to obtain one of the most popular defensive handguns in the country.
Common Use and the Legal Challenge
Handguns in common use for lawful purposes sit at the core of Second Amendment protection under District of Columbia v. Heller. Glock and Glock-style pistols are not rare or unusual. They are among the most produced and owned handguns in America. Gun-rights groups argue that banning future acquisition of an entire family of common handguns because a criminal could attach an already-illegal part is not a regulation consistent with the nation’s historical tradition of firearms regulation.
The National Rifle Association, Second Amendment Foundation, Firearms Policy Coalition, a Maryland dealer, and individual residents filed suit shortly after the bill was signed. In Bathras v. Moore, they sought a preliminary injunction in July 2026 to block enforcement before January 1, 2027. Maryland House Republicans separately asked the Justice Department’s Civil Rights Division to review the statute, citing similar concerns raised about California’s parallel law. No final ruling on the merits had issued as of mid-September 2026.
Maryland’s position is that the law is a public-safety measure aimed at firearms that can be “readily converted,” that current owners are grandfathered, and that exceptions exist for law enforcement. The state police will compile the official list of covered models. Whether a federal court treats the statute as a handgun ban or as a narrow regulation of a subset of pistols will determine whether the sales freeze takes effect.
What This Means for Owners and Dealers
Until January 1, 2027, covered pistols may still be sold and transferred in Maryland, subject to existing Handgun Qualification License, waiting-period, and background-check rules. After that date, commercial traffic in those models stops inside the state unless a court intervenes. Dealers cannot stock them for Maryland buyers. Owners who want to sell will face a thin market limited mostly to family transfers or out-of-state sales through licensed channels.
The law does not confiscate existing pistols. It does change what a Marylander can buy next year and what an owner can do with a pistol already in the safe. It also adds administrative uncertainty: the State Police list has not yet been published, and the statutory definition turns on technical features (cruciform trigger bar, removable blocking tab, “common household tools”) that most buyers cannot evaluate at a glance.
None of that changes the legal status of the switch itself. Possessing or installing a Glock switch remains a serious federal and state offense. Maryland already had that prohibition on the books. SB 334 does not close a gap in the law against conversion devices. It restricts an unconverted, commonly owned semiautomatic pistol because of what a criminal might do with a separate, already-illegal part.
That is the distinction the statute draws, and the distinction now before the courts.