Hi, this is probably going to sound a bit odd, but i'm planning to write a story just for fun (probably featuring zombies) and i just wanted the gun combat in it to be as realistic as possible. These questions are probably pretty tedious, so sorry bout that. And i know next to nothing about firearms as well. 1) How often go handguns, sub-machine guns, shotguns and rifles jam? 2) What sort of maintenance would be done beforehand to ensure a gun is in good condition; such as cleaning the barrel and stuff. 3) Just in general (not necessarily against zombies ) how effetive is a handgun compared to say a rifle, shotgun or sub-machine gun in terms of accuracy and power? 4) Do people often actually carry seperate catridges only or keep only a few catridges and spare bullets? 5) What other problems might occur in a combat situation, even for people trained with guns. Sorry bout the exhaustive list , thanks.