Revealing mistake: When Hamer goes to the gun store and obtains all of his weaponry, the gun counter guy and boy carry the weapons out to his vehicle. The weight of the weapons would be too much for one to carry all at the same time and the boy is supposedly carrying that large box of ammo, which would have contained over a thousand rounds, but he's carrying it like a box of feathers.
Continuity mistake: There is no radio antenna on Frank's car until they stop at an intersection. When it's said there's a radio in the car is the first and last time you can see an antenna.
Factual error: There's a modern car in the background as soon as they arrive in Dallas. (00:32:50)
Continuity mistake: When Hamer goes to the gun store and acquires all the guns, his car is parked in a different spot when he leaves. There is no bench to the front left when he enters the gun store. When he is leaving his old partner is sitting on a bench to the left front of the car. The sandbags and vegetable boxes are also positioned differently in relation to the car. (00:27:50)
Factual error: When Maney and Frank are chasing Bonnie and Clyde in a dusty field, Maney (Woody Harrelson) fires his Colt Peacemaker revolver. His first shot is CG since the gun fires without him cocking the hammer. The Colt Peacemaker is a single action revolver, requiring the hammer to be cocked each time in order to fire the gun.
Factual error: The 1934 Ford of Bonny and Clyde's tires are late model car tires, too wide for that time period. (00:12:15)
Continuity mistake: Hamer's pig goes back in the house through a front door that is ajar. After Gladie gives Hamer her shopping bag she opens a closed front door. (00:11:50)
Continuity mistake: When he squats down over the guy who got his brains beat in with a bat, his hands are resting near his knees. Then they change angles and he is holding wall with right hand. Then they quickly go back to original view and he has his hands the original way again.