the amount of ammo onhand depends alot on the weapon you have, in reality in all you have is a handgun 500 rounds is plenty. if all you have is a handgun, and you think you are going to stop a crowd, all you are really doing in preparing for your own version of custers last stand. A rifle is a far better weapon to begin with. For a hunting/long range rifle 100 rounds is a good start. Anyone that has been in combat will tell you an assualt rifle, while the best choice, can consume 1,000 rounds, in a hairy furball, in one engagement. Keep in mind, in some instances, ammo is currency is well. Have a nice day