AUSTIN, TEXAS – After successfully firing a gun made with a 3-D printer over the weekend, a University of Texas law school student hopes to refine the prototype and ultimately distribute online files so anyone can make one.

The test firing amid the national gun control debate was immediately called "stomach-churning" by one U.S. senator and has prompted nervous calls for legislation to outlaw such guns. The first prototypes were all plastic, but 25-year-old Cody Wilson says he has made modifications including adding 6 ounces of steel so metal detectors can spot it.

He also has obtained a manufacturing license from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

Ultimately, Wilson wants to distribute downloadable files that can be plugged into a 3-D printer.

"It's about empowerment of the individual over political hierarchy," he said.

Wilson, who one year ago co-founded Defense Distributed, the online collective managing the Wiki Weapon Project, said the .380-caliber pistol "behaved exactly as we expected it would" during the test.

The Austin office of the Bureau of Alcohol, Tobacco, Firearms and Explosives confirmed that Wilson has the required licenses to legally manufacture the gun and the ammunition for it.

Sen. Chuck Schumer, D-N.Y., said the technology means anyone "can open a gun factory in their garage" and announced that he and Rep. Steve Israel, D-N.Y., are introducing legislation to outlaw 3-D printed guns.

Schumer said the guns can pass unnoticed through metal detectors, violating the Undetectable Firearms Act of 1988.

Others worry that felons, mentally ill people, or terrorists could use the technology to manufacture firearms and potentially explosives.

Wilson calls Schumer's anticipated legislation "pernicious" and outdated because airport detectors are more sophisticated. One of his plastic guns is unlikely to ever make it on a plane undetected, he said.

Plus, his current prototype has steel in it.

"I understand the concern, but there is a bit of misdirection," Wilson said. "This gun is detectable by backscatter X-ray and digital imaging and all the other conventional modern forms of imaging."

Next step, a prototype

His next step is to refine the prototype, which was successfully fired Saturday on private property in Lockhart, Texas. The test-firing video has been posted on YouTube. The gun is called the Liberator and is mostly made of bulky white plastic. Wilson is hoping to streamline it and make improvements.

Wilson developed the idea with a friend in March 2012 and raised $2,000 in 22 days through the crowdsourcing website Indiegogo.com. The company then froze their account because of the weapon concerns. A company that had loaned Wilson a 3-D printer reclaimed it a day later because of legal concerns.

But through media attention, Wilson said, the group reached its target of $20,000 on Sept. 19.