WASHINGTON — With 3-D printers increasingly able to produce plastic weapons, the House voted Tuesday to renew a 25-year-old prohibition against firearms that can evade metal detectors and X-ray machines.
On a voice vote, the House passed a bill to renew the Undetectable Firearms Act for another decade.
The Senate could vote on the bill next Monday when it returns from a two-week Thanksgiving recess. The law is due to expire the following day.
Some Senate Democrats have mounted an attempt to amend the law to require plastic guns to have at least one metal piece for making it fire. But with the National Rifle Association opposed to the measure, the House bill is likely to pass the Senate unchanged, particularly going into an election year when many lawmakers would prefer to avoid a new fight over gun legislation.
Representative Robert Scott, a Virginia Democrat, said passage of the bill Tuesday “should not be interpreted that the statute should not be updated for the duration” of the new 10-year ban.
Senator Charles Schumer, a New York Democrat who has championed gun reform laws this year, has pledged to introduce legislation to close what he and others describe as a dangerous loophole.
Just prior to Tuesday’s vote, the NRA issued a statement saying it opposes any expansion of the law, including applying it “to magazines, gun parts, or the development of new technologies.”
Another group, the conservative Gun Owners of America, opposed renewing the law, saying it wouldn’t stop criminals intent on printing weapons.
“They’ve just spent all year trying to effectively destroy the gun lobby,” Mike Hammond, legislative counsel of the small group, said of Democrats. “So why in heaven’s name, given this intransigence, should we give them this Christmas present?”
The expiring law forbids firearms that aren’t spotted by airport X-ray screening machines or metal detectors. To meet that requirement, today’s plastic guns often come with a metal part that can be detached and isn’t necessary for the weapon to function.
Lawmakers and law enforcement officials alike have long been concerned that technological advances could allow for the production of guns that don’t have any metal, first passing the ban on such weapons in 1988 under President Reagan. It has been renewed twice since then.
Today 3-D printers can spray repeated, thin layers of plastic or other materials to create objects from toys to automobile parts to medical devices. They are being used increasingly by companies, researchers, and hobbyists, and the technology is constantly improving.
The use of 3-D printers to manufacture guns received heightened attention in May when Cody Wilson, then a University of Texas law student, posted blueprints online for using the printers to make the Liberator pistol, which he says he designed. Wilson, founder of Defense Distributed, a nonprofit that advocates the free distribution of information on 3-D printed weapons, was ordered by the State Department to take down the instructions after two days because of allegedly violating arms export controls, he said.
By then, the plans had been downloaded more than 100,000 times and they remain available on file-sharing websites, he said.
‘‘If you want to do this, it’s plainly obvious there’s no one standing between you, your computer, and your 3-D printer. Anyone can make this gun,’’ Wilson said Monday.
According to the Bureau of Alcohol, Tobacco, Firearms, and Explosives, which regulates gun manufactures and sales, 3-D printers can range in cost from $1,000 to $500,000, though they can also be leased.
ATF tested two plastic guns from different plastics using Wilson’s design earlier this year. One of the weapons exploded when it was fired. The second one shot off eight rounds before ATF stopped the test. Reluctant to oppose renewal and anger allies, Democrats have backed a renewal of the ban, despite their preference to also require permanent metal components that would make plastic firearms more detectable.