Ammunition and magazine laws in Pennsylvania

§ 6302. Sale or lease of weapons and explosives.
(a) Offense defined.--A person is guilty of a misdemeanor of the first degree if he sells or causes to be sold or leases to any person under 18 years of age any deadly weapon, cartridge, gunpowder, or other similar dangerous explosive substance.
(b) Exception.--The provisions of subsection (a) shall not prohibit hunting by minors under 18 years of age permitted under Title 34 (relating to game).

(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).