Absolutely. More specifically were all 8 casings recovered, recovered from that roof and in pattern that would reflect ejection from that weapon.
I am no longer certain, there actually was only one shooter shooting, having seen audio ballistic analysis of weapon report, and sonic crack, as measured from a fixed microphone directly in front of stage, recorded by a major news network, and analyzed by non-government graphic analysis to determine time of flight and distance from stage. While I am certain the dead kid did majority of shooting, I cannot rule out 1 possibly two more people shooting, not to mention the sniper that took out the would be assassin kid. I look forward to official analysis to clarify or refute independent analysis, so far. I am a skeptic, withholding judgement until all evidence analyzed, made public and explained. I don't like trump, but actions such as this are totally unacceptable, and must be thoroughly investigated to answer real world questions, to insure this does not happen again.