GUNSWhat Can the ATF Do About Converted Machine Guns?

By Alain Stephens and Champe Barton

Published 16 June 2022

Auto sears have become increasingly popular among criminals, and have been tied to dozens of shootings by extremists, mass shooters, and drug traffickers. Lawmakers are clamoring for action on auto sears, and history leaves clues about what approach the ATF might take.

On April 11, more than 40 members of Congress signed a letter urging the Bureau of Alcohol, Tobacco, Firearms and Explosives to take action on the proliferation of the auto sear, a small device that makes a semiautomatic gun capable of emptying an entire magazine with a single pull of the trigger. 

Auto sears, as The Trace and VICE News reported in March, have become increasingly popular among criminals, and have been tied to dozens of shootings by extremists, mass shooters, and drug traffickers. This April, a gunman armed with a converted Glock handgun opened fire in downtown Sacramento leaving six dead and 12 wounded.

“The ATF is the primary federal regulator for firearms and should be playing quarterback here,” said Representative Jake Auchincloss, a Democrat from Massachusetts, who signed the letter. “They should be enforcing the law on the ground. But they should also be putting some of the liability for the misuse of these weapons —  if that misuse is predictable and apparent — onto the manufacturers.”

In their letter, members of Congress asked the ATF to be more explicit in calling conversion devices illegal and to crack down on them. They’re also asking the agency to put a stop to the companies “pushing the legal limits on these devices.” But finding an effective solution may be difficult. Industry insiders and law enforcement officials interviewed for this story questioned whether the agency has the power to do more than it’s already doing. 

Machine guns have been subject to strict federal regulation for nearly 90 years. The National Firearms Act of 1934 required anyone who owned a fully automatic weapon to register it with the government and pay a $200 tax, equivalent to about $4,000 today. These requirements significantly drove up the cost of owning a machine gun, and as a result ownership became rare. 

The auto sear was invented in the 1970s as a way for gunsmiths and hobbyists to fashion their own automatic weapons away from the watchful eyes of the government. With some elbow grease, an auto sear can convert popular semiautomatic rifles and handguns into machine guns. But in 1981, the ATF ruled that an auto sear is, legally, a machine gun. Without the proper licensing and taxes paid, possession of one of the devices is punishable with up to 10 years in prison.