C-Bug.

[Munch]

first of all, how do you know it's a bug? and second... how the hell do YOU know if it wasnt intended to be like it is? you can't bring "oh its not realistic" into this.. thats like saying getting hit with a car without going to the hospital or jetpacks are realistic. On every GTA game so far.. if you shoot one bullet, switch to another, and switch back.. the ammo refills.

True. Plus one of the popular things in every GTA are the bugs. As soon as people get GTA, they like spotting bugs and see how to put that bug to good use. So I think Rockstar intend to keep these little glitches for that purpose to increase people's fun.