I'd say about the time your dad was comfortable with you using his power tools on your own, looking out for your mother while he was away, or driving his car. And there's no age or law that defines that. It's an individual right and an individual responsibility. If more androgynous maletards stopped buying guns to make up for the fact that they lack spines, and actually acted like men on the small scale, - meaning at home, with their kids, in their businesses, - we'd never be in this ridiculous ****ing shitshow of a situation where everyone is asking stupid questions, and waiting for elected authorities to grant us permission to do normal things, in the first place.