Factual error: When Walter Goggins fires a LAW at the church from next to the vehicle, the back-blast from the rocket would have shattered the car's windows, and flying glass fragments would likely have injured the occupant. The show depicts neither outcome.
Continuity mistake: In the scene with the horse trainer, the character has a wedding ring on, then doesn't, then does, and finally doesn't again. (00:30:40 - 00:32:50)
Continuity mistake: As Raylan sits down opposite the thug, who says "I just take orders", his gun is held vertically. Cut to a shot from the front and it's on its side. (00:25:00)
The Hammer - S1-E10
Character mistake: Raylan Givens tells Judge Reardon that he carries a ".45 Glock" but this is untrue. Throughout the series with the exception of the beginning of the first episode Raylan Givens carries a Glock 17, which is only chambered in 9mm parabellum. His backup can be seen to be a Glock 26 which is also in 9mm.