Reduce the prevalence of ammo. Right now peoples lives are worth so much less then the ammo it takes to kill them. And its a major factor in why banditry is so easy. To accomplish this separate the concept of ammunition and magazines. For instance you have one G17 and one magazine for it. you then find 4 9mm rounds and load them in the magazine. Later you might find 2 more 9mm rounds and add them to the magazine for a total of 6. And if you did not have a magazine you could only fire one round and then have to reload/put a new round in the chamber. (You keep empty magazines on reload of course since they are so valuable)