I won't carry a gun until I am comfortable and confident in my ability with a particular weapon and the weapon has demonstrated reliability. That may vary with any given weapon. I have a xd40sc that I have put in excess of 1,000 rounds through that I am very comfortable with my abilities and it as a reliable weapon. I just traded a gun for a brand new Glock 36 that I only have 100 rounds through and I am not confident in my abilities with it at this point. How ever many rounds it takes for me to be confident in my abilities with it is however many it takes before I will carry it. If that day never comes, then so be it.