Ammunition and magazine laws in Arizona

A. Except as provided in subsection C of this section, a person who sells or gives to a minor, without written consent of the minor's parent or legal guardian, a firearm, ammunition or a toy pistol by which dangerous and explosive substances may be discharged is guilty of a class 6 felony.
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C. The temporary transfer of firearms and ammunition by firearms safety instructors, hunter safety instructors, competition coaches or their assistants shall be allowed if the minor's parent or guardian has given consent for the minor to participate in activities such as firearms or hunting safety courses, firearms competition or training.

(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).