Colorado prohibits the sale, transfer and possession of a “large-capacity magazine.”1

“Large-capacity magazine” means:

  • A fixed or detachable magazine, box, drum, feed strip, or similar device capable of accepting, or that is designed to be readily converted to accept, more than 15 rounds of ammunition;
  • A fixed, tubular shotgun magazine that holds more than 28 inches of shotgun shells, including any extension device that is attached to the magazine and holds additional shotgun shells; or
  • A nontubular, detachable magazine, box, drum, feed strip, or similar device that is capable of accepting more than eight shotgun shells when combined with a fixed magazine.2

“Large-capacity magazine” does not include:

  • A feeding device that has been permanently altered so that it cannot accommodate more than fifteen rounds of ammunition;
  • An attached tubular device designed to accept, and capable of operating only with, .22 rimfire ammunition; or
  • A tubular magazine that is contained in a lever-action firearm.3

A large-capacity magazine that is manufactured in Colorado after July 1, 2013, must include a permanent stamp or marking indicating that the large-capacity magazine was manufactured or assembled after July 1, 2013.  The stamp or marking must be legibly and conspicuously engraved or cast upon the outer surface of the large-capacity magazine.  The Colorado Bureau of Investigation may create rules for implementing this requirement, including additional identification information on each large-capacity magazine.4

Exceptions – A person may possess a large-capacity magazine if they owned the large-capacity magazine on or prior to July 1, 2013, and maintain continuous possession of the magazine.5  When a person charged with illegal possession of a large-capacity magazine claims to fall under this exception, the burden of proof is on the prosecution to prove otherwise.6

The large-capacity magazine ban does not apply to military or police agents that carry a firearm in the course of their official duties.  The ban also does not apply to an entity or employee of an entity engaged in the manufacture of large-capacity magazines within Colorado solely for transfer to any licensed gun dealer that sells large-capacity magazines exclusively to the armed forces, government agencies, a retailer operating outside of the state of Colorado, or a foreign national government approved by the U.S. for such transfers.7

See our Large Capacity Ammunition Magazines policy summary for a comprehensive discussion of this issue.

Notes
  1. Colo. Rev. Stat. § 18-12-302(1)(a). A violation of this prohibition will be punishable as a Class 2 misdemeanor, and it is a Class 6 felony to possess a large-capacity magazine during the commission of a felony or crime of violence. Colo. Rev. Stat. § 18-12-302(1)(a), (c). ⤴︎
  2. Colo. Rev. Stat. § 18-12-301(2)(a). ⤴︎
  3. Colo. Rev. Stat. § 18-12-301(2)(b). ⤴︎
  4. Colo. Rev. Stat. § 18-12-303. ⤴︎
  5. Colo. Rev. Stat. § 18-12-302(2)(a). ⤴︎
  6. Colo. Rev. Stat. § 18-12-302(2)(b). ⤴︎
  7. Colo. Rev. Stat. § 18-12-302(3). ⤴︎