The actor killed in the final sequence can be seen reacting twice to being shot in different angles BEFORE the shot is actually fired.
At about 43:00 when Gargen and Donelli are going to see (second) top brass Phillips a henchman of Phillips whom Gargen had recently knocked out in an alley, opens the door. In the next shot when Gargen and Donelli are entering the house the henchman has vanished.
Despite using a six-shot revolver, one of the characters in the final reel fires eleven shots without reloading.
When Joe is on a dark street waiting to meet his tire plant boss, he lights a cigarette. He has his right hand up to block the wind, but it is obviously concealing a small light, as it stays lit for a beat or two after the match in his other hand is moved away and goes out.
The cylinders in the revolvers in the final two scenes must have had at least 9 or 10 chambers. Raft's gun had already been fired 4 or 5 times at the laundry before he fired at least as many at the theater. Dobkin fired at least 9 times before dying once and another time before dying again.