I heard the audio and it was full auto. In fact he was rotating to other full auto guns. From the report ,I would guess .223 . Full autos are illegal so laws won’t help. My guess is disassembled AR-15 Which are easily packed and hidden in larger luggage and golf bags etc.
This shows great logistical planning and supply, I believe a full auto can fire 900 RPM so if he was up there 10 minutes in firing mode 50% of the time , he fired over 4000 rounds. There will be quite an investigation into the supply , One report is he had 10 weapons. The reason I suspect ISLAM is their hatred of what they view as Western decadence. This was the case in Orlando at the homosexual bar. In San Bernadino they struck an office party celebrating the birth of our Lord. I’m inclined to be persuaded that this was a jihad attack but time will tell.
People like you are so ignorant. Don't post unless you know something about guns. Unless you live in a slave state, full auto is legal but registered.