This Bible contradiction is from the Skeptic's Annotated Bible.

Verses

The chief priests bought the potter's field.

Matthew 27:6 View context

And the chief priests took the silver pieces, and said, It is not lawful for to put them into the treasury, because it is the price of blood.

Judas bought the potter's field.

Acts 1:18 View context

Now this man purchased a field with the reward of iniquity; and falling headlong, he burst asunder in the midst, and all his bowels gushed out.