If you watch it frame by frame you can see when scuffle starts the guy in the orange bends his arm to raise the pistol, as soon as he does that the other guy grabs the gun by the barrel with his left hand, he then steps to the side and behind the guy in the orange shirt and throws him to the ground. He then transfers the gun to his right hand and starts shooting.I've watched this about 20 times, and I still can't figure out how the gun gets from the orange shirts right hand into his left hand to be taken away by purple shirt guy.