I have some military training, and I majored in mathematics and know something of probability.
It is true that accuracy at 500 yards with assault rifles shooting on a simulated fully automatic would suck.
But the shot grouping is not necessarily a function of accuracy, but of rate of fire and luck. If one person is hit by three bullets and another by 3...out of dozens of bullets spayed all at once, there is no evidence that the bullets weren't distributed fairly randomly in the area around them.
Moreover his contention that a non-military person would lack the logistical skill to smuggle that much equipment in is just stupid. Just about anybody could figure out how to just hide stuff in a lot of suitcases and take a lot of suitcases up. When they hell have you seen hotel personel checking suitcases when one checks in? Or counting them? Or counting how many trips one makes? He wasn't boarding an airplane.
You’re wrong. Mr. Mathematics.
Having fired AR-15 and AR-10 platforms, I can assure you that there is muzzle walk on the weapons in single shot and in rapid fire situations. If you are targeting at 500-600 yards range even a millimeter of walk on the muzzle drastically effects the impact location. You’re not talking about a 1mm rise at the muzzle being a 1mm rise at the target, because its not a straight shot. Even with high velocity rounds such as the 5.56mm nato round, its still a ballistic shot. This is well documented and proven science. At 500 yards, the 5.56 (M193) drops roughly 60 inches by the time it reaches its target. Altering the muzzle by 1mm, since its not a flat alteration, but an arced alteration, can make the impact distance between rounds many feet apart. That is to say, three rounds on one target that is moving at that range is not possible except under the most controlled circumstances. Rapid fire is nowhere near the controlled circumstance required, so this is pretty much an impossible feat.
See: https://en.wikipedia.org/wiki/Minute_and_second_of_arc#Firearms
My guess is that these stories are exaggerations made by people under extreme duress\stress. This is a lot more likely.
I do agree that the 22,000 people in attendance made it difficult to miss.
Exactly. Anyone who has cleaned an AR-15 has separated the upper and lower (less than a one-minute job with essentially no tools needed). Those two parts fit in most suitcases. Smuggling a suitcase into a hotel room does not require a James Bond, not even a Jason Bourne. Smuggling a couple dozen suitcases in over a span of several days is just as easy.
I saw some holes in a metal building - iirc there were 3 or 4 tight together - like a few inches and almost touching. That seemed odd to me. I am not familiar with automatic weapons, but I figure even with such a high rate of fire the muzzle moves a bit after each round. Of course it would be even odder if 4 snipers were all shooting at that same indistinct spot on the building!
“Moreover his contention that a non-military person would lack the logistical skill to smuggle that much equipment in is just stupid.”
Correct. Most people have made a simple move from a residence. You can move a bunch of stuff with one person.