2021 Colorado Code
Title 18 - Criminal Code
Article 12 - Offenses Relating to Firearms and Weapons
Part 3 - Large-Capacity Ammunition Magazines
§ 18-12-301. Definitions

As used in this part 3, unless the context otherwise requires:

1. “Bureau” means the Colorado bureau of investigation created and existing pursuant to section 24-33.5-401, C.R.S.
2. 1. “Large-capacity magazine” means:
      1. 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 fifteen rounds of ammunition;
      2. A fixed, tubular shotgun magazine that holds more than twenty-eight inches of shotgun shells, including any extension device that is attached to the magazine and holds additional shotgun shells; or
      3. 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 mean:
      1. A feeding device that has been permanently altered so that it cannot accommodate more than fifteen rounds of ammunition;
      2. An attached tubular device designed to accept, and capable of operating only with, .22 caliber rimfire ammunition; or
      3. A tubular magazine that is contained in a lever-action firearm.

History. Source: L. 2013: Entire part added,(HB 13-1224), ch. 48, p. 144, § 1, effective July 1.

This section and §§ 18-12-302 and 18-12-303 represent a reasonable exercise of the state's police power and thus are constitutional because the discrete legislative purpose in enacting the statutes, to reduce the number of people who are killed or shot in mass shootings, lies within the state's police power; the statutes are reasonably related to the legitimate governmental purpose of reducing deaths from mass shootings; and limiting magazine size to fifteen rounds of ammunition does not unreasonably burden the right to self-defense. Rocky Mountain Gun Owners v. Polis, 2020 CO 66, 467 P.3d 314.

A magazine “designed to be readily converted to accept” more than fifteen rounds, as defined in subsection (2)(a)(I), is one that would be objectively understood as purposely created or intended for the purpose of being converted to accept more than fifteen rounds. The phrase “designed to be” must mean something other than merely “capable of”. A magazine “designed” to be readily converted to accept more than fifteen rounds requires an intent or purpose that a magazine merely “capable” of being so converted does not. Rocky Mountain Gun Owners v. Polis, 2020 CO 66, 467 P.3d 314.