Continuity mistake: When Barry the Baptist is putting the guy's head in the water asking him for the money, notice that the first shot is Barry holding his neck, then in the next shot he is holding his shirt.
Continuity mistake: After all the shooting at Eddy's place, Rory and Plank shoot each other, Rory was standing up and then we hear a body slump to the floor, (just after the two shots). When we see the interior again, Rory is on the couch. Falling on the couch wouldn't have made that noise and I doubt he would have been able to pick himself up after a point blank blast with a shotgun.
Continuity mistake: The last scene, when Tom is to throw the rifles out from the bridge, before doing so, he unwraps them to take a final look. Then he wraps them again, takes them out of the car and throws. When he realizes that the rifles are lying on the other side of the rail he tries to grab them. Then we can see that they are tied together with two strings, although Tom only wrapped them.
Continuity mistake: When Dog throws Winston the keys to open the cage, the trajectory of the keys as shown would have had Winston catching the keys at waist height. But he catches the keys at a chest high level.
Continuity mistake: When Dog and his gang are about to get their drugs hijacked, watch as Dog sits down and picks up the phone. He turns right around, enough to see Bacon, who doesn't move. But in the next shot, Bacon moves his shotgun to point it at Dog while Dog is still turning his head. (01:03:00)