Ammunition and magazine laws in Idaho

No person, firm, association or corporation shall sell or give to any minor under the age of sixteen (16) years any powder, commonly called gunpowder, of any description, or any dynamite or other explosive, or any shells or fixed ammunition of any kind, except shells loaded for use in shotguns and for use in rifles of twenty-two (22) caliber or smaller, or any firearms of any description, without the written consent of the parents or guardian of such minor first had and obtained. Any person, firm, association or corporation violating any of the provisions of this section shall be deemed guilty of a misdemeanor.
[18-3308, added 1972, ch. 336, sec. 1, p. 912; am. 1994, ch. 131, sec. 14, p. 300.]

(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).