Ammunition and magazine laws in District of Columbia

(a) No person shall possess ammunition in the District of Columbia unless:
(1) He is a licensed dealer pursuant to subchapter IV of this unit;
(3) He is the holder of a valid registration certificate for a firearm pursuant to subchapter II of this chapter; except, that no such person shall possess one or more restricted pistol bullets;
(b) No person in the District shall knowingly possess, sell, or transfer any ammunition feeding device that is, in fact, a large capacity ammunition feeding device regardless of whether the device is attached to a firearm.
(c) For the purposes of this section, the term "large capacity ammunition feeding device" means a magazine, belt, drum, feed strip, or similar device that has a capacity of, or that can be readily restored or converted to accept, more than 10 rounds of ammunition. The term "large capacity ammunition feeding device" shall not include an attached tubular device designed to accept, and capable of operating only with, .22 caliber rimfire ammunition.

(c) For the purposes of this section, the term "large capacity ammunition feeding device" means a magazine, belt, drum, feed strip, or similar device that has a capacity of, or that can be readily restored or converted to accept, more than 10 rounds of ammunition. The term "large capacity ammunition feeding device" shall not include an attached tubular device designed to accept, and capable of operating only with, .22 caliber rimfire ammunition.

(2) “Ammunition” means cartridge cases, shells, projectiles (including shot), primers, bullets (including restricted pistol bullets), propellant powder, or other devices or materials designed, redesigned, or intended for use in a firearm or destructive device.
(13A)(A) “Restricted pistol bullet” means:
(i) A projectile or projectile core which may be used in a pistol and which is constructed entirely (excluding the presence of traces of other substances) from one or a combination of tungsten alloys, steel, iron, brass, bronze, beryllium copper, or depleted uranium;
(ii) A full jacketed projectile larger than .22 caliber designed and intended for use in a pistol and whose jacket has a weight of more than 25% of the total weight of the projectile; or
(iii) Ammunition for a .50 BMG rifle.

(x)(1) It shall be unlawful for a person to sell, deliver, or otherwise transfer to a person who the transferor knows or has reasonable cause to believe is a juvenile—
(A) a handgun; or
(B) ammunition that is suitable for use only in a handgun.
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(5) For purposes of this subsection, the term "juvenile" means a person who is less than 18 years of age.

Small Arms Ammunition: Ammunition is classified as a Division 1.1, 1.2, 1.3, or 1.4 explosive, depending on the degree of hazard. Ammunition that is regulated as a Class 1 explosive and designed to be fired from a pistol, revolver, rifle, or shotgun, as well as associated primers and blank cartridges (including those designed for tools) and propellant powder for use in any firearm, is prohibited from mailing.
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Shotgun Hulls, Empty Casings, Nonmetallic Shotgun Hulls, or Casings Without Primers: These articles are not classified as explosives or hazardous materials under 49 CFR and, therefore, are mailable, subject to the applicable mailing rules (refer to 224).