Depends on what gun it is. Mycenterfire riflesevery 20-40 rounds. My handguns after every range use(Normally 50-200 rounds per gun). My rimfires every couple hundred rounds. Shotguns are every time they get more then 10 rounds through them. All my guns will get cleaned before any long storage also. Even if i shoot 1 round out of my 22 mag and its gettign put away for a few months it gets a really good cleaning.