A fastener driving device includes a nose assembly having a drive channel, a magazine for carrying a supply of fasteners through a feed channel along a feed channel direction toward the nose assembly, and one or more mechanisms for preventing undesirable movement of fasteners. The mechanisms may include a first stop pawl and a second stop pawl for preventing the supply of fasteners from moving along a direction opposite to the feed channel direction. The stop pawls may extend from a common side of the feed channel and pivot on a common axis. The mechanisms may also include a first nail stop, a second nail stop and/or a movable nail stop.