Banning untraceable guns made with a 3D printer would close a dangerous loophole in Washington’s gun laws, supporters said Tuesday.

“Printable guns are a way to undermine the will of the people,” said Bharat Shyam, former state chief information officer, noting the Legislature and voters have approved background checks for all firearms purchases. “It’s only common sense. We need to regulate it.”

But a gun rights supporter called the need for a state ban against so-called ghost guns “lunacy at best” because federal law already requires that guns have serial numbers, and plastic firearms might explode from the pressure when a round is fired.

“You’ve got a bomb in your hand,” Mike Silvers told the Senate Law and Justice Committee. “You’re not going to hurt the other guy; you’re going to hurt yourself.”

Tuesday’s hearing was the committee’s second go-round on the issue of untraceable firearms. It passed a similar bill in January, but that proposal never was put to a vote in the full Senate. The House, however, passed its version of a ban on ghost guns earlier this month, sending the issue back to the committee with only minor differences.

The bill would ban the manufacturing or use of an untraceable firearm, which can be made on a 3D printer with so little steel that metal detectors may not catch it. A company in Texas created a computer program to make a plastic gun on a 3D printer, but the federal government banned it from distributing the program on the internet for several years. When the federal government dropped its objection, Washington and several other states sued to block distribution, and that case is still in court.

Rep. Javier Valdez, D-Seattle, the bill’s sponsor, said it was important for Washington “to get out in front of this problem.” People should feel safe when they go to the airport, courthouse or stadium, he said.

Luis Berbesi, of Shoreline, said the law doesn’t have exceptions for law-abiding people like him who enjoy long-distance shooting for sport and sometimes have to re-create components for their guns. One of his dreams is to design and create his own handgun, but the law wouldn’t allow him to do that, he said.

“This law would make me a criminal overnight,” Berbesi said.

Tony Wilson, a Thurston County resident who described himself as a supporter of the constitutional right to bear arms, said court rulings have said those rights can be limited and the state should limit untraceable firearms.

“Standard firearms are sufficient for anyone to exercise his or her Second Amendment rights,” Wilson said.

The committee will decide in the coming days whether to send this version of the ghost-gun bill to the full Senate.