Chuck Versus the Fake Name - S3-E8
Factual error: When they first bring Grueber into Castle, Sara states that "he is one of five people who can hit a target from half a mile away." Half a mile is 880 yards. Basically every person who has graduated from (or likely everyone who has been selected for) sniper school in any military in the world should be able to do this. (00:05:20)