Firearm technologies have advanced significantly in the last several decades, which has prompted state laws and regulations regarding firearm hardware and ammunition. Colorado law bans selling, transferring, and possessing high-capacity magazines. Additionally, beginning in 2024, state law also makes it unlawful to possess a firearm, frame, or receiver without a serial number to address the use of so-called “ghost guns.”
In Colorado, local governments may pass bans on selling certain kinds of hardware and ammunition. Denver, Vail, and Boulder each have city-specific ordinances that ban semi-automatic rifles with detachable magazines.
Applicable State Laws
Colorado Revised Statutes (C.R.S.) are posted on the Colorado Legal Resources Public Access Website.
Unserialized Firearms and Firearm Components: C.R.S §18-12-111.5 (SB 23-279)
- Effective Date: June 2, 2023.
- Current owners of unserialized firearms or components (“ghost guns”) have until January 1, 2024, to have firearms and components imprinted with a serial number.
- The following are prohibited for unfinished firearm frames or receivers without a serial number:
- Possessing or transporting.
- Selling, transferring, or purchasing.
- Manufacturing.
- Engaging in any of the above actions is unlawful and is classified as a Class 1 misdemeanor, except for a second or subsequent offense, which is a Class 5 felony.
- Individuals who currently own a firearm, frame, or receiver that they personally manufactured and which lacks a serial number from a federal firearms licensee must have it imprinted with a serial number by January 1, 2024.
- The law restricts the CBI from approving the transfer of a firearm to a person convicted of a misdemeanor violation within the past five years. Individuals convicted of the felony are prohibited from possessing firearms or other weapons.
- Federal firearms licensees can imprint a serial number on firearms, frames, or receivers. The law establishes a process and requirements for licensees to serialize firearms.
- Additionally, the law defines machine gun conversion devices, often called switches, as dangerous weapons.
Prohibiting Large-Capacity Ammunition Magazines : C.R.S §18-12-301 (HB 13-1224)
- Prohibits the sale, transfer, or possession of an ammunition-feeding device that is capable of accepting, or that can be readily converted to accept, more than ten rounds of ammunition or more than five shotgun shells (large-capacity magazine).