The Marksman Carbine has a 30-round STANAG magazine but in-game it is shown as only having 24 rounds in the magazine.
The Assault Carbine fires 5mm rounds when it should be firing 5.56mm ammunition instead.
In Nipton, Boxcars tells the Courier that Caesar's Legion broke his legs in the lottery. If the Courier shots Boxcars he gets up and runs.