The House of Delegates passed a sweeping ban on the sale of pistols that can be easily converted into machine guns Wednesday, advancing legislation that could take one of the nation’s most popular handguns off the market in Maryland.

Both chambers now have approved the bill and it is expected to head to Gov. Wes Moore soon. If signed into law, Maryland would be the second state in the country to ban the sale of “machine-gun convertible pistols,” a term for handguns that can be converted into automatic weapons with a tiny device known as a Glock switch.

A similar law in California, which has been dubbed a “Glock ban‚” is being challenged in court, and gun rights groups say they would challenge Maryland’s law in court.

The bill does not single out Glocks, but it would ban the sale of semiautomatic pistols that use a “cruciform trigger bar,” a component primarily used in Glock pistols and copycat weapons. The cruciform trigger bar is the mechanism that limits the gun to a single round of ammunition per trigger pull, and can be disabled to make the gun fire multiple rounds with one pull of the trigger.

Switches are already illegal under Maryland and federal law, but supporters of the legislation say that lawmakers should go further and require gun manufacturers to make their products harder to retrofit. Maryland’s bill would ban future sales of pistols that can be converted into machine guns, but would not require current Glock owners to get rid of their guns or modify them.

“If you currently own one, you can keep it,” said Del. Nicole Williams, a Prince George’s County Democrat and a sponsor of the bill, during debate on the House floor. “No one is taking your gun away from you. After this, if Glock modifies its design, you can go purchase that newly designed gun.”

The sale ban would not apply to law enforcement officers, retired law enforcement or members of the military.

Glock discontinued some of its handgun models last year and replaced them with designs intended to prevent the use of switches, but the newer models still use a cruciform trigger bar and would be banned under the Maryland legislation, said Mark Pennak, the president of the gun-rights group Maryland Shall Issue.

Pennak said he “fully intends” to challenge the Maryland ban in court if it becomes law.

Banning Glocks and other handguns that use the same trigger mechanism could impact 30 percent to 40 percent of pistol sales at Hafer’s Guns in Hagerstown, shop owner Tim Hafer said.

“That would be a significant decrease in sales,” said Hafer, who has store locations in Maryland and in West Virginia. Hafer said he’s concerned about his Maryland store surviving if the ban passes, while his West Virginia business will be unaffected.

“It has nothing to do with stopping crime,” Hafer said. “It has everything to do with control.”

Several law enforcement agencies in Maryland supported the bill, including the Baltimore Police Department, citing the use of machine-gun convertible pistols in crime. The handgun used in an October 2023 mass shooting at Morgan State University had been modified with a Glock switch, which allowed the shooter to fire rounds more quickly. Five people were injured in that shooting.

“The danger posed by a firearm modified in this manner is difficult to overstate,” BPD said in written testimony. Once the trigger is pulled on a converted weapon, it will “continue to fire, sometimes at a rate of up to 1,200 rounds per minute, until there is no more ammunition.”

Baltimore and the state of Maryland also sued Glock last year, claiming the company was responsible for a rise in illegal machine guns by selling pistols that can be converted using simple household tools. The lawsuit is pending in Baltimore City Circuit Court.

Gun safety advocates applauded the bill’s progress and its focus on “weapons of war.”

“This bill focuses on prevention by stopping these convertible weapons at the source before they can devastate our communities,” Monisha Henley, senior vice president for government affairs at Everytown for Gun Safety, said in a statement.

Banner reporter Pamela Wood contributed to this story.