Cal. Penal Code § 27505

(a) No person, corporation, or firm shall sell, loan, or transfer a firearm to a minor, nor sell a handgun to an individual under 21 years of age. (b) Subdivision (a) shall not apply to or affect the following circumstances: (1) The sale of a handgun, if the handgun is an antique firearm and the sale is to a person at least 18 years of age. (2) The loan of a firearm to a minor by the minor’s parent or legal guardian, if both of the following requirements are satisfied: (A) The minor is being loaned the firearm for the purposes of engaging in a lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, or a motion picture, television, or video production, or entertainment or theatrical event, the nature of which involves the use of a firearm. (B) The duration of the loan does not exceed the amount of time that is reasonably necessary to engage in the lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, or a motion picture, television, or video production, or entertainment or theatrical event, the nature of which involves the use of a firearm. (3) The loan of a semiautomatic centerfire rifle or handgun to a minor by a person who is not the minor’s parent or legal guardian, if all of the following requirements are satisfied: (A) The minor is accompanied by the minor’s parent or legal guardian when the loan is made, or the minor has the written consent of the minor’s parent or legal guardian, which is presented at the time of the loan, or earlier. (B) The minor is being loaned the firearm for the purpose of engaging in a lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, or a motion picture, television, or video production, or entertainment or theatrical event, the nature of which involves the use of a firearm. (C) The duration of the loan does not exceed the amount of time that is reasonably necessary to engage in the lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, or a motion picture, television, or video production, or entertainment or theatrical event, the nature of which involves the use of a firearm. (D) The duration of the loan does not, in any event, exceed 10 days. (4) The loan of a firearm other than a semiautomatic centerfire rifle or a handgun to a minor who is 16 years of age or older, by a person who is not the minor’s parent or legal guardian, if all of the following conditions apply: (A) The loan is with the express permission of the minor’s parent or legal guardian. (B) The minor is being loaned the firearm for the purpose of engaging in a lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, the nature of which involves the use of a firearm. (C) The duration of the loan does not exceed the amount of time that is reasonably necessary to engage in the lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, the nature of which involves the use of a firearm. (D) The duration of the loan does not, in any event, exceed 5 days, unless express permission is provided in the manner described in subparagraph (A) of paragraph (3), in which case the duration of the loan shall not, in any event, exceed 10 days. (5) The loan of a firearm other than a semiautomatic centerfire rifle or a handgun to a minor under 16 years of age by a person who is not the minor’s parent or legal guardian, if all of the following conditions apply: (A) The loan is with the express permission of the minor’s parent or legal guardian. (B) The minor is being loaned the firearm for the purpose of engaging in a lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, the nature of which involves the use of a firearm. (C) The duration of the loan does not exceed the amount of time that is reasonably necessary to engage in the lawful, recreational sport, including, but not limited to, competitive shooting, or agricultural, ranching, or hunting activity or hunting education, the nature of which involves the use of a firearm. (D) The minor accompanied at all times by a responsible adult. (E) The duration of the loan does not, in any event, exceed 5 days, unless express permission is provided in the manner described in subparagraph (A) of paragraph (3), in which case the duration of the loan shall not, in any event, exceed 10 days.