I will be telling my age, but when I started carrying my S&W Model 645 on duty I went to qualify at the Sheriff’s Office Range. The senior firearms instructor was inspecting my weapon before I attempted to qualify. Without asking he disassembled my 645, removed the magazine safety and handled it back to me. He looked at me and said, “You may only get one chance to get a round off at your attacker while reloading in a fire fight”. That was it. I still carry it today since I am an old head now. And he retired and they just recently named the new firearms complex after him. So I am guessing he knew what he was talking about back in the day.