The article, Las Vegas Shooting 1-Oct-2017: An acoustic analysis, was updated to address recent information made available in the LVMPD Preliminary Investigative Report which was released within the last couple of days. While the report may raise more questions then it answers, it does not alter the single shooter conclusion drawn in my article.
Although the report does not specify which weapon or weapons were used in the shooting, it does catalog the weapons, among which were 13 .223 caliber AR-15 rifles, all outfitted with bump-stocks. These AR-15s were apparently the only rifles outfitted with bump-stocks and therefore, since we know the alleged shooter, Stephan Paddock, was using a bump-stock equipped rifle, the cartridge i happened to pick for my ballistic analysis is at least the correct caliber. This is further corroborated in the report where it catalogs approximately 1050 expended .223 casings, all found in room 32-135. Eight .308 rounds were found in room 32-134, the smaller room that Paddock allegedly rented under the name of his girlfriend, Marilou Danley. According to the report, all these rounds appear to be single shots that were directed at the airport fuel tank.
What is most interesting to me regarding the report is the bits of information regarding Paddocks physical and mental health. The report verifies that Paddock was very likely taking diazepam (Valium) and may have been taking a lot of it and may have been mixing the drug with alcohol. Given the highly dangerous laundry list of side-effects for these types of drugs, including potentially violent and unusual behavior, this alone could be the motive for the shooting, though i still think there may be much more to the story.
Here is the press conference regarding the release of the report: