This story was originally published by KUNC.
By Lucas Brady Woods, KUNC
Colorado gun owners and sellers could soon have to contend with sweeping new restrictions as three gun-control proposals approach final passage in the Colorado legislature.
The most significant measure, Senate Bill 25-003, would create some of the strictest gun-ownership rules in the country.
It would make it illegal to buy, sell and manufacture most guns that use detachable magazines, unless a person has a special permit. A wide range of rifles, shotguns, pistols and some handguns would be affected by the bill. To obtain a permit, they would have to go through up to 12 hours of safety training and get approval from their local sheriff.
Supporters of the measure claim it’s needed to strengthen the state’s decade-old ban on magazines with more than 15 rounds. They argue restricting access to detachable magazines will limit the damage caused during mass shootings. The devices allow people to reload and fire bullets more quickly, and have been used by shooters in recent years, despite the existing high-capacity magazine ban.
The bill’s lead sponsor is Democrat Sen. Tom Sullivan, whose son Alex was killed during the 2012 mass shooting at an Aurora movie theater. That shooter used a 100-round detachable magazine.
“This will be about the next one, possibly the first one for the next mass shooter in our state,” Sullivan said. “The next one you buy in Colorado will have an attached magazine that corresponds to the limits of the type of firearm.”
The measure would not take effect until August 2026 and would not affect any guns that people already own.
Another measure, House Bill 25-1133, would raise the minimum purchasing age for ammunition to 21, in most cases. It includes exceptions for people at shooting ranges, those who have a hunter education certification or hunting license, members of the military, and people who are currently between 18 and 21.
“House Bill 1133 will keep ammunition out of the hands of people too young to legally purchase firearms, which is critical to public safety,” said bill sponsor Sen. Cathay Kipp, a Fort Collins Democrat, referring to a 2023 state law that raised the minimum gun-purchasing age to 21.
The third proposal, House Bill 25-1238, would tighten regulations on the hundreds of gun shows that take place in Colorado each year.
It would prohibit anyone under 18 years old from entering gun shows without a parent or guardian present and would require shows to ensure that each firearm sale complies with the state’s three-day waiting period for gun purchases. It would also require gun show promoters to share a security plan with local law enforcement, implement security measures and have liability insurance.
Republicans fiercely oppose the bills, arguing they infringe on Coloradans’ constitutional rights, target law-abiding gun owners over criminals and would drive gun shows and gun dealers out of the state.
They have been especially critical of Senate Bill 3, the measure restricting the use of detachable magazines. “It is fiscally irresponsible, undermines our constitutional protections, and attempts to transform an unalienable, God-given right into a privilege granted by bureaucracy,” said Rep. Ty Winter of Trinidad, the second-highest ranking Republican in the House.
The measures have gone through over a hundred hours of debate so far and have one final legislative hurdle to clear.
The chambers have already passed them on a preliminary basis with some changes. Now, the opposite chamber has to vote to approve those amendments before sending the measures to Gov. Jared Polis’ desk.
Senate President James Coleman, a Democrat, is hopeful Republicans won’t drag out the final vote, as they have done throughout the legislative session when it comes to gun legislation.
“Couldn't tell you what they're going to do, but I think that they definitely made their points on how they feel about the policy,” Coleman said.
But just because the legislature passes the bills, doesn’t mean lawmakers’ work on the policies is done. Coleman pointed out they still have to make sure these measures are implemented effectively.
Even if they become law, they could face challenges in court. Gun-rights group Rocky Mountain Gun Owners has already said it plans to sue over Senate Bill 3 if it’s signed.
Copyright © 2025 KUNC
This story was produced by the Capitol News Alliance, a collaboration between KUNC News, Colorado Public Radio, Rocky Mountain PBS, and The Colorado Sun, and shared with Rocky Mountain Community Radio and other news organizations across the state. Funding for the Alliance is provided in part by the Corporation for Public Broadcasting.
