In his official report, Charles Winstead stated that he fired "the division .45 caliber automatic" at Dillinger. At that time, what later became the FBI was called the "Division of Investigation". It didn't become the FBI until several months later.

According to Bryan Burrough in "Public Enemies", Winstead fired three shots, Clarence Hurt fired twice, and agent Ed Hollis fired once. Dillinger was hit four times, two of which were minor wounds. Purvis carried a Colt .38 revolver that night, but fired no shots.

Also according to Burrough, the agents involved agreed among themselves to not discuss details of the shooting. For many years, the Bureau refused to release any information, but it was generally agreed that Winstead fired the fatal shot which struck Dillinger in the back of the neck as he ducked and ran.

Hoover wrote a letter to Winstead commending his (Winstead's) actions, which letter acknowledged that Winstead's shots had brought Dillinger down. Apparently there have been extensive efforts by collectors to determine the serial number of Winstead's gun, but no dice. The Bureau's records for that era were not very complete, and the Bureau was not inclined to release much information.

Apparently, Chicago PD had been told nothing about the Bureau's stakeout, did not participate, and in fact almost blew the whole operation when a couple of carloads of uniformed CPD officers responded to reports of "suspicious-looking men" hanging around the theater.

Interestingly, agent Hollis was one of the two agents murdered by Nelson during Nelson's final gunfight in November of that year.