The only guns designed to be breech loaded are rifles and shotguns. Asking someone to "disarm" their gun when entering your house increases the possibility of accidents. Why couldn't he just put it on top of a cabinet or somewhere out of the reach of children? Dropping the slide at full force on a loaded mag isn't going to cause an accidental discharge, the same as de-cocking. However all firearms need to be pointed in a safe direction when performing these maneuvers. Preferably outside the house.