After several hours of impassioned testimony mostly from opponents to a measure to ban ammo magazines of more than 10 rounds, Colorado’s House Judiciary Committee late Tuesday night passed the measure.

But the bill, sponsored by state Rep. Rhonda Fields, D-Aurora, was amended by her colleagues to increase that limit to 15 rounds.

State Rep. Mike McLachlan, D- Durango, who sits on the committee, offered the amendment to, he said, allow citizens to protect themselves.

“Fifteen is a reasonable number, and this is what I’m going to ask in my amendment,” McLachlan said.

Other amendments to the bill also were expected.

The House Judiciary Committee consists of seven Democrats and four Republicans,

Former Bureau of Alcohol, Tobacco and Firearms agent David Chipman said a magazine ban is essential.

“It will keep killers from being killing machines,” Chipman said.

In its form at the time of publication, House Bill 1224 prohibits the sale or possession of gun magazines that hold more than 10 rounds or more than five shotgun shells.

The bill says that if an individual already owns a high-capacity magazine on the effective date of the bill’s becoming law, then that individual may retain it. Prosecutors would bear the burden of proof that an owner violated the new stricture.

However, manufacturers would still be able to produce these magazines within the state.

Charles Robles traveled from Colorado Springs and said had it not been for a high-capacity magazine, he would not be alive.

“It helped me engage the three men who were shooting at me,” said Robles in reference to a 2002 Memorial Day robbery at his small business. “I was shot five times, but I was able to save my life and fend off my attackers. ”

Doug Smith, chief operating officer of the Colorado-based ammunition magazine manufacturer Magpul, said the measure would force his company to leave Colorado and take with it an estimated $85 million in potential spending this year.

“Passage would devastate the company,” he said of the measure.

State Rep. Daniel Kagan, D-Cherry Hills Village, who chairs the committee, said he did not want Magpul to leave the state.

“I want to protect manufacturing in Colorado,” Kagan said.

But that didn’t sit well with Lee Reedy, who traveled from Brighton with his wife to testify.

“It’s hypocritical,” Reedy said in an interview. “On one end they’re saying we want the jobs and revenue from producing these magazines, but on the other end, they’re saying if you live in Colorado, then you can’t possess one.”

Kurtis Lee: 303-954-1655, klee@denver post.com or twitter.com/kurtisalee