Ammunition and magazine laws in Minnesota

Subd. 1b.
Felony; furnishing to minors.
Whoever, in any municipality of this state, furnishes a minor under 18 years of age with a firearm, airgun, ammunition, or explosive without the prior consent of the minor's parent or guardian or of the police department of the municipality is guilty of a felony and may be sentenced to imprisonment for not more than ten years or to payment of a fine of not more than $20,000, or both. Possession of written evidence of prior consent signed by the minor's parent or guardian is a complete defense to a charge under this subdivision.

(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).