I agree he certainly must have had other contacts that were aware of his plans, if not actual real time support in the massacre, but the "gun running" angle is harder for me to accept. He would have not have been limited to use weapons tied to his name, or limited himself to weapons bought from stores that sell to hobbyists. I realize that made them all trace back to him, for cover, but he didn't even have the most powerful arms a citizen could buy for a mission like this, since it appears he mostly used AR-15's. Just my thoughts, and enjoying your posts.
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He bought 33 weapons from Oct 2016 to Sept 2017, mostly rifles.
He brought a large number to the hotel room; and in fact it appears he did use a lot of weapons in the shooting.
It appears he had a stack of rifles with bump-stocks pre-loaded with Surefire 100-rd magazines, and as soon as he emptied one or it jammed, he picked up another rifle and carried on.
But even taking that into account, there seemed to be quite a few extra weapons and mags beyond that.
I lean toward the theory that there was a second person in the room. Perhaps a Filipino (muslim?) acquaintance who was an employee at one of the hotels there. Who knows. But anyway, my theory is that this other person fired out the second window for a few minutes and then sat down to monitor the cameras and listen to the police scanner (I don’t see how Paddock could monitor the cameras and shoot at the same time).
He probably mentioned to Paddock hearing the police getting warm from the scanner and then ran out, and Paddock was supposed to follow. The second person left the door ajar. Paddock finished up shooting, grabbed his bag or whatever and started to follow but that’s when the security guard happened upon the scene and noticed the door ajar (per the Sheriff). Paddock closed the door and shot at the security guard and then realizing he would never actually make the escape, shot himself.
I suspect there were others who were a part of this who may have gotten cold feet or some other reason and some of the weapons were for them. Also, Paddock had some plan to escape the hotel and probably also to continue life living on the lam under an alias like his father did, and there may have been a network of some kind to help him had he made it out of the room. Maybe he was going to make his way to the Philippines and meet up with his girlfriend eventually.