Revealing mistake: When the sheriff is handing out "silver bullets", in the wooden box holding the ammo you can see that none of the cartridges have primers. The cartridges will never fire without a primer. (01:21:20)
Continuity mistake: The wooden box (holding the "silver bullets" that the sheriff is handing out) has no markings on the side from a distance, but when the camera zooms in to see the ammo, you can see heavy black marks like someone crossed out a name and address, and you can also see a paper label partially torn off the box with writing blacked out. Then when the camera zooms back again, and the deputy picks up the box, the side of the wooden box is blank again. (01:21:20)