Once a niche concern for the gun control movement, machine gun conversion devices like the “Glock switch” have become a legislative flashpoint in red and blue states alike.
A Glock switch (sometimes called a “button” or a “giggle switch”) is a machinegun conversion device (MCD) that can be attached to the rear of the slide of a handgun, transforming a semi-automatic pistol into a selective-fire machine pistol capable of fully automatic fire. Contrary to narratives put forward by the corporate press, they are not made or sold by Glock. On top of that, these switches are already an illegal aftermarket item.
In New Mexico, law enforcement and prosecutors supported a measure to ban machinegun conversion devices, while in Alabama, Gov. Kay Ivey (R) made this issue a legislative priority. This year, elected officials in both states — one governed by Democrats, the other by Republicans — enacted new laws making these devices illegal. Currently, at least half of U.S. states have similar statutes prohibiting these devices, a number that has increased over the past decade. These state laws mirror longstanding federal regulations that generally prohibit machineguns and components that can transform semiautomatic weapons into automatic weapons.
Federal law has prohibited the possession of machineguns manufactured after 1986, with exceptions for law enforcement, the military, and certain licensed dealers. Nearly all conversion devices are illegal because they were produced after this cutoff. Individuals convicted of possessing machineguns or conversion devices can face prison sentences of up to 10 years.
Between 2012 and 2016, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) seized only 814 machinegun conversion parts. That number surged to 5,454 from 2017 to 2021. In January, the Biden administration reported that 12,360 suspected machinegun conversion devices had been recovered across the nation and submitted to the ATF during a roughly 34-month period ending in October 2024. Five states — Florida, Illinois, Montana, North Dakota, and Texas— made up nearly half of these recoveries.
Alabama is the most recent state to ban machinegun conversion devices. A law recently signed by Republican Governor Kay Ivey makes it a felony, punishable by up to 10 years in prison, to possess parts intended to convert pistols into machine guns. The bipartisan effort in Alabama followed police reports allegedly linking machinegun conversion devices to deadly shootings, including a September incident in Birmingham that left four dead and 17 injured.
In February, Democratic New Mexico Governor Michelle Lujan Grisham signed a law making the possession of a weapon conversion device a felony with a penalty of up to three years in prison. Similar measures have passed in the New Jersey General Assembly and are pending in other states. Last year, Republican Virginia Governor Glenn Youngkin signed a law banning auto sears, but recently vetoed a bill that would have expanded a current ban on “trigger activators” to encompass additional devices that increase the firing rate of semiautomatic weapons.
Gun control advocacy groups like Everytown for Gun Safety argue that state laws can sometimes offer a more practical route to prosecution for machinegun conversion possession than federal law, but they are pushing for even stricter measures. Everytown is supporting legislation in California, Maryland, and New York that would ban the sale of pistols that can be converted into machineguns.
“That really puts the pressure where it belongs — on the manufacturers that are making money off of guns that they know can be readily turned into machineguns,” observed Nick Suplina, Everytown’s senior vice president for law and policy.
Several cities and states, such as Baltimore, Chicago, Minnesota, and New Jersey, have filed lawsuits against Glock, alleging the company makes pistols that can be converted to automatic weapons.
Pro-gun organizations like Gun Owners of America have long criticized efforts to ban these devices. They have opposed state bans on machinegun conversion devices, describing them as “duplicative” and “pure virtue signaling.” GOA’s federal affairs director, Aidan Johnston, argues that automatic firearms have legitimate uses, such as controlling invasive species like feral hogs, and that ownership of converted firearms does not inherently indicate criminal intent.
In Pennsylvania, GOA has previously mobilized in opposition to a bill introduced by State Rep. Barry Jozwiak (R) to ban Glock switches, deeming it a betrayal of gun owners. The organization emphasized that federal law already regulates these devices under the National Firearms Act (NFA), rendering state-level bans superfluous. GOA accused Jozwiak of aligning with “anti-gun Democrats” and argued that such laws disproportionately punish lawful gun owners while failing to deter criminals.
The National Association for Gun Rights (NAGR) has also fought state efforts to expand definitions of machineguns to include Glock switches or convertible pistols. In response to New York’s proposed bill (S.9225), which sought to prohibit pistols capable of being modified with conversion devices, NAGR issued a cease-and-desist letter to the state senate. The group argued the legislation would effectively “ban an entire manufacturer from the state” by targeting Glock handguns, despite their lawful design and widespread use. NAGR’s Northeast Regional Director, Angelo Veltri, criticized the bill for creating a new category of “convertible pistols,” which he asserted would unjustly classify commonly owned firearms as machineguns based solely on their potential for illegal modification.
NAGR President Dudley Brown further asserted that such laws embolden other states to adopt similar infringements, calling the proposal part of a broader “radical gun control” agenda.
With lawsuits mounting and laws tightening, the once-obscure Glock switch is now squarely in the legal and political crosshairs. Time will only tell if these measures snowball into a major federal campaign to further crack down on gun rights.
About José Niño
José Niño is a freelance writer based in Austin, Texas. You can contact him via Facebook and X/Twitter. Subscribe to his Substack newsletter by visiting “Jose Nino Unfiltered” on Substack.com.
