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Prohibit Auto Sears, Bump Stocks, and Other Rapid-Fire Devices

Solutions

Prohibit Auto Sears, Bump Stocks, and Other Rapid-Fire Devices

What does it solve?

Fully automatic machine guns—those that fire bullets in rapid succession with a single pull of the trigger—and the parts used to create them have been tightly regulated under federal law since the 1930s.1US Bureau of Alcohol, Tobacco, Firearms and Explosives, “National Firearms Act,” April 7, 2020, https://www.atf.gov/rules-and-regulations/national-firearms-act. However, the gun industry and third-party sellers continue to produce devices that make it easy to convert semi-automatic firearms into illegal machine guns in a matter of minutes.

These devices, including auto sears, bump stocks, and binary triggers, dramatically increase a gun’s rate of fire, making them attractive to mass shooters and other criminals, and pose an increased danger to the public. Some of these devices are small in size and simple in design which makes them easy to manufacture, or simply 3D print.1Alain Stephens and Keegan Hamilton, “The Return of the Machine Gun,” The Trace, March 24, 2022, https://www.thetrace.org/2022/03/auto-sear-gun-chip-glock-switch-automatic-conversion/. They are also often falsely marketed online as innocuous products.2Alain Stephens and Keegan Hamilton, “The Return of the Machine Gun,” The Trace, March 24, 2022, https://www.thetrace.org/2022/03/auto-sear-gun-chip-glock-switch-automatic-conversion/.

Tragically, these devices have been recovered at numerous crime scenes across the country, including at the largest and deadliest mass shooting in modern US history,3US Bureau of Alcohol, Tobacco, Firearms and Explosives, “National Firearms Commerce and Trafficking Assessment (NFCTA): Crime Guns – Volume Two: PART VII: Recommendations and Future Enhancements,” January 2023, https://www.atf.gov/firearms/docs/report/nfcta-volume-ii-part-vii-recommendations/download. where 60 people were shot and killed and over 400 more were shot and wounded during the Route 91 Harvest music festival in Las Vegas.4Las Vegas Metropolitan Police Department, “Criminal Investigative Report of the 1 October Mass Casaulty Shooting: LVMPD Event Number 171001-3519,” August 3, 2018, https://www.lvmpd.com/home/showpublisheddocument/134/638298568313170000; “What Is a Bump Stock and How Does It Work?” New York Times, February 27, 2024, https://nyti.ms/43NEi6b; Rio Yamat and Ken Ritter, “FBI Documents Give New View into Las Vegas Shooter’s Mindset,” AP, March 30, 2023, https://apnews.com/article/las-vegas-shooter-9bbd180cf3aa6d3ea1a37bbfb7144ae1. States can take action by enacting laws prohibiting the manufacture, sale, and possession of machine gun conversion devices as well as any rapid-fire devices that increase a semi-automatic weapon’s rate of fire.

Which states have specific laws prohibiting bump stocks?

Everytown legal analysis, 2024

How it works

Rapid-fire devices effectively convert semi-automatic weapons into machine guns.

There are three major types of rapid-fire conversion devices:

  • Auto sears, often in the form of “Glock switches,” alter the trigger mechanisms of semi-automatic pistols and rifles, enabling the guns to continuously fire rounds as long as the trigger is depressed and the gun has ammunition. These devices can allow pistols to fire at rates of up to 1,200 rounds per minute.1U.S. Attorney’s Office for the Northern District of Texas, “Fort Worth Manufacturer Charged in Glock Switch Case,” press release, November 18, 2022, https://www.atf.gov/news/press-releases/fort-worth-manufacturer-charged-glock-switch-case. 
  • Bump stocks are replacement shoulder attachments for semi-automatic rifles, particularly AR- and AK-style rifles, that harness the recoil from firing to allow a shooter to fire shots in rapid succession—up to 800 rounds per minute.2Michael Smith and Polly Mosendz, “The Making of a Millionaire and a Massacre,” Bloomberg, October 11, 2017, https://www.bloomberg.com/news/articles/2017-10-11/the-bump-stock-millionaire-and-the-las-vegas-massacre. 
  • Binary and forced-reset triggers are drop-in replacement triggers for semi-automatic firearms, including AR- and AK-style firearms, that allow shooters to fire one shot when they pull the trigger and another when they release the trigger, effectively doubling the rate of gunfire.

The recoil caused by these devices can make the firearms equipped with them hard to control and shoot accurately, making them even more dangerous.

Nearly all of the firearms used by the mass shooter in Las Vegas were equipped with bump stocks, which enabled him to fire over 1,000 rounds of ammunition in minutes.3Of the 24 firearms recovered from the shooter’s hotel room, 15 were fired by the gunman. Of those 15 fired, 12 were AR-15s equipped with bump stocks. Las Vegas Metropolitan Police Department, “Criminal Investigative Report of the 1 October Mass Casaulty Shooting: LVMPD Event Number 171001-3519,” August 3, 2018, https://www.lvmpd.com/home/showpublisheddocument/134/638298568313170000. Following the shooting, states across the country—including those with Republican governors at the time4Massachusetts, Florida, Maryland, and Vermont.—enacted laws to prohibit bump stocks. The ATF also took steps to prohibit the manufacture, sale, and possession of bump stocks through a rule clarifying that the federal definition of “machine gun” includes bump stocks. The rule took effect in March 2019.5US Department of Justice and Bureau of Alcohol, Tobacco, Firearms and Explosives, “Bump-Stock-Type Devices,” Federal Register 83, no. 246 (December 26, 2018): 66514–54, https://www.govinfo.gov/content/pkg/FR-2018-12-26/pdf/2018-27763.pdf. Unfortunately, in its dangerous June 2024 decision in Garland v. Cargill, the Supreme Court threw out the ATF rule.6Garland et al. v. Cargill, 602 U.S. ____ (2024), https://www.supremecourt.gov/opinions/23pdf/22-976_e29g.pdf. While 16 states and Washington, DC, have specific and clear prohibitions on bump stocks under state laws, the Supreme Court’s decision in Cargill effectively legalized bump stocks in as many as 34 states.7Some of these states have laws prohibiting machine guns that could be interpreted to include bump stocks, but the laws do not explicitly state bump stocks are prohibited.

While some states have prohibited auto sears and similar conversion devices under laws related to machine guns for years, other states—including those with majority-Republican legislatures or Republican governors8Indiana, Mississippi, and Virginia.—have recently taken action to codify such prohibitions. 

Prohibiting rapid-fire conversion devices would help prevent people from using them to convert semi-automatic weapons into machine guns and address the growing threat of automatic gunfire and the mass shootings carried out with firearms equipped with these deadly devices.

By the numbers

Victories

You might be wondering…

  1. 1 Are Bump Stocks Machine Guns?