Coloradans who want to buy ammunition magazines could be limited to 15 rounds under a measure lawmakers in the state Senate gave initial approval to Friday night.

The measure now heads to a final floor vote on Monday — moving it a step closer to being signed into law by Gov. John Hickenlooper, who has indicated his support of the legislation.

House Bill 1224 passed through the House chamber by a 34-31 margin in February, and was originally sponsored by state Rep. Rhonda Fields, D-Aurora.

To open floor debate Friday afternoon, lawmakers passed an amendment that bans any shotgun magazines that hold more than 28 inches of shotgun shells. Shells vary in size, and originally the bill outlawed any magazines with more than eight shells.

Republicans said the amendment makes a flawed bill better, as it now doesn’t ban what they described as “common shotguns” from Coloradans.

Much of the floor session devoted to the measure consisted of Republicans assailing it as a job killing bill that would impact the state’s economy because an Erie-based ammunition manufacturer has vowed to depart the state if it passes.

Sen. Mary Hodge, D-Brighton, the bill’s sponsor in the Senate, stressed Friday several recent shooting sprees — including ones in Aurora and Connecticut — were committed with gun magazines that held more than 15 rounds.

“This bill is mirroring an attempt to reduce the slaughter.” Hodge said on Friday. “I’m trying to keep constituents safer.”

Ellen Roberts, R-Durango, agreed with Hodge, saying that no one should turn a blind eye to mass shootings, but she is in opposition to the bill.

“It’s a fallacy to think that by passing it crime will not happen,” Roberts said. “You can’t legislate away evil.

Republican lawmakers offered an amendment that allowed military veterans to possess ammunition magazines of more than 15 rounds, but Democrats rejected the measure.

During the discussion Hodge drew some criticism from Republicans who argued she had implied that some veterans suffer from mental illness.

Republicans have also argued that HB 1224 would impact Colorado’s economy and have cited the Erie-based ammunition manufacturer, Magpul as a clear example.

For several weeks the company has vowed to leave the state if the bill is passed and have argued that staying in Colorado and selling to individuals outside of the state, but not to local residents, is counter to the company’s values.

Moreover, the company notes that because of the way magazines are manufactured the law would in essence be unenforceable.

Founder and CEO Richard Fitzpatrick testified in a House commitee Monday that some of Magpul’s magazines have a floor plate that is removable for cleaning purposes, but could be converted to house an additional magazine.

Sen. Bill Cadman, R-Colorado Springs, offered testimony in the floor debate that “reveals members of SEAL Team 6 used Magpul magazines” in the killing of Osama Bin Laden.

Cadman cited photos from the book “No Easy Day,” which was written by a former Navy SEAL.

“This is a patriotic company that we’re going to force to leave the state,” Cadman said.

Meanwhile, Rep. Andy Kerr, D-Lakewood, noted in an interview outside the Senate chamber that Colorado has always been ranked highly for having business friendly climate.

“I’ve met with them (Magpul) and I’ve talked with them and I understand the decisions that they are saying they might have to make. At the end of the day it’s their decision what to do with their company,” Kerr said.

Hodge on Friday was the only Senate Democrat to offer floor comments in support of the measure.

What to watch for: Some senators say they are undecided on the measure, including Angela Giron, D-Pueblo; and Linda Newell, D-Littleton. If any of them decide to vote against the bill, it would likely die, as Cheri Jahn, D-Wheat Ridge, and Lois Tochtrop, D-Thorton, say they will vote no.

If HB 1224 passes out of the Senate unamended, it then moves on to Gov. John Hickenlooper’s desk where he said he’ll sign it into law.

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

Staff writer Nic Turiciano contributed to this report.