zlacker

To add to this, having had quite of bit of firearms experience both semi and auto, the real limiting factors are, as mentioned, controllability and ammo.

With a 30 round mag and a cyclic rate of 700 rounds per minute (AR-15 mods run 700-1000 RPM), you get a little over 2 seconds of trigger time. That assumes you don't experience a jam, which is very likely with an AR-15 variant modified for automatic fire, and because of the weight distribution and recoil deflection, you won't hit anything you aim at after the second round leaves the chamber. So, if they are packing fully auto AR-15 mods, I'd be wayyyyy less concerned than if they were using semi automatic.

>>crafti+(OP)
> I'd be wayyyyy less concerned than if they were using semi automatic.

In general, yes. To play devil's advocate though, accuracy/controllability is not really needed if your goal is just to spray as much lead as possible into a densely crowded area from, say, a hotel room above.

Such domestic terrorist events are extremely rare, but I would guess in these specific cases where the goal is to spray as many bullets per second as possible into a crowd, full auto + large magazine is going to kill more people than semi auto.

>>umvi+1p
Semi auto fires as fast as you can tap the trigger, they still fire plenty fast. Test out how long it takes you to get through 30 clicks on your mouse. Now keep in mind with the automatic, by your third or fourth shot your aim might be 10 feet higher than where you set off aiming at the start of the burst, and you can see how even in crowds a semi automatic weapon would be far more dangerous as you could control where the rifle is pointed.

>>umvi+1p
Late reply, sorry. I'd say that in the domestic terrorism situation you describe, even someone completely untrained would still be more deadly taking aimed shots than with full auto or auto bursts. With auto, most of those 30 rounds would impact the ground unless they were shooting into a really, really dense mass of people, and even then you'd have many shots that would be grazing or non lethal hits. And by the time the second magazine went in, people would be clearing out fast.

With a large magazine it would be a different story though, you are right about that. This is why I think that it's good to have fully auto by design weapons be illegal (think the SAW, or the M240), along with magazines above 30 rounds.