Other mistake: Jack takes the moonshine to Floyd Banner and sells 200 gallons @ $5 a gallon, ie. $1,000. When he gives the money to Forrest he tells him it's $2,000 minus his commission.
Audio problem: In the scene where Jack Bondurant is loading jars into the back of the truck, Floyd Banner is driven into town and screeches to a halt nearby. Although the tyres screech which is characteristic of tyres stopping suddenly/losing traction on Tarmac or cement, the car is on a loose dirt road.
Continuity mistake: In the scene where Jack Boundurant is getting threatened/punched by Charlie Rakes inside the home of Cricket Pate: Rakes is holding Boundurant and severely damaging a single side of his face. In the next scene Boundurant appears with his brothers and the wound appears on the other side of his face.
Factual error: At the beginning of the film you see the car coming around a bend and see a double yellow line in the center of the road. White center lines were used as early as 1917 but weren't widely used until the early 50s and center yellow wasn't mandated until 1971.
Revealing mistake: When The Deputy Charley Rakes goes to Cricket's house and attacks Jack, you see Charley throw Jack down the steps outside the house. If you look closely, you can see he lands on something really soft and spongy like a mattress which is hidden under the foliage on the ground to break his fall. When Charley walks down the steps towards Jack, you see him walk on it, which again looks really soft and spongy.
Visible crew/equipment: In the long shot of the vehicle approaching the camera near the start of the film, a crewman's hand can momentarily be seen in the extreme upper left hand corner of the frame. (00:02:55)
Continuity mistake: Directly after the scene when Jake goes to the church and leaves after his feet are watched, we see that he leaves his shoe at the church. The next scene at crickets house where he gets beaten up by the deputy, he has both shoes again. (02:00:00)
Factual error: When Jack turns on the radio in the V8 roadster, I don't think they had instant-on. I'm quite sure it had vacuum tubes.