How many bullets can a machine gun shoot at a time?

Answer 1

In all fully automatic machine gun designs, only one bullet can come out of the barrel at at a time, but the gun will continue to fire bullets as long as the trigger is held and the weapon still has ammunition.

Rates of fire vary widely depending on the type of machine gun, with the slowest ones firing at about 200 rounds per minute, and the faster ones firing over 6,000 rounds per minute, at least as long as the supply of ammunition lasts. Note that the fastest conventional automatic weapons have multiple barrels and are the "Gatling gun" type of weapon. There are newer weapons around that have firing rates that dwarf those posted here, but they are not using standard cartridges as ammunition. These "metal storm" weapons stack bullets and charges (stacked rounds) in the back of a gun barrel, one on top of another. The rounds are fired electronically, and firing rates of hundreds of thousands of rounds per minute are easily achieved. A primary difference here is that each barrel in a multiple-barrel weapon of this type can send a round down range at the same time. All the rounds in multiple barrels can be fired in a mere fraction of a second, exhausting the ammunition supply. Anyone thinking about it would expect these guns to present a challenge when it comes to reloading them. Once all the rounds from a given setup were fired, more rounds have to be "stacked" in the back of the gun barrel(s). Though the military is looking into these weapons, the obvious limitation precludes broad deployment, at least in the immediate future.