Quoted:
As long as they are in your presence, anyone who is not a conveicted felon or otherwise prohibited from possessing firearms should be able to use your guns.

[It's legal to]lend that assault weapon to another if all the following apply:
(A) The person to whom the assault weapon is lent is 18 years of age or over and is not in a class of persons prohibited from possessing firearms by virtue of Section 12021 or 12021.1 of this code or Section 8100 or 8103 of the Welfare and Institutions Code.
(B) The person to whom the assault weapon is lent remains in the presence of the registered possessor of the assault weapon, or the person who lawfully possesses an assault weapon pursuant to subdivision (i).
(C) The assault weapon is possessed at any of the following locations:
(i) While on a target range that holds a regulatory or business license for the purpose of practicing shooting at that target range.
(ii) While on the premises of a target range of a public or private club or organization organized for the purpose of practicing shooting at targets.
(iii) While attending any exhibition, display, or educational project that is about firearms and that is sponsored by, conducted under the auspices of, or approved by a law enforcement agency or a nationally or state recognized entity that fosters proficiency in, or promotes education about, firearms.