California Code, Health and Safety Code - HSC § 12102

(a) Smokeless powder is intended only for hand loading of small arms ammunition of .75 caliber or less.

(b) Black sporting powder is intended for loading of small arms or small arms ammunition of .75 caliber or less.

(c) All such powder is for private use and not for resale, and, in the case of black sporting powder, there shall be no gift, delivery, or other disposition to another person.

(d) The storage, use and handling of such smokeless and black powder conforms to rules, regulations, or ordinances of authorities having jurisdiction for fire prevention and suppression in the area of such storage, use, and handling of such explosives.