6-12. As viewed from the rear, in what direction does the rotor move when an M61A1 automatic gun is operating? 1. Clockwise 2. Counterclockwise 3. Vertically 4. Horizontally 6-13. On an M61A1 automatic gun, what cam moves the firing pin forward against the primer of the round? 1. The locking cam 2. The contact cam 3. The firing pin cam 4. The unlocking cam 6-14. What component of an M61A1 automatic gun ejects the empty case from the gun? 1. The ejector 2. The guide bar 3. The extractor lip 4. The ejection cam 6-15. On  an  M61A1  automatic  gun,  what  sequence of   actions   is   performed   by   the   breech-bolt assembly during one full firing cycle? 1. Feed, chamber, ram and lock, fire, unlock, extract, and eject 2. Feed,   chamber,   lock   and   fire,   unlock, extract, and eject 3. Ram  and  chamber,  lock  and  fire,  unlock, extract, and eject 4. Load  and  lock,  fire,  unlock,  extract,  and eject 6-16. On   an   M61A1   automatic   gun,   the   clearing cycle begins when what event occurs? 1. When the pilot initiates the clearing switch 2. When the clearing solenoid is deactivated 3. When the clearing solenoid is energized 4. When the spent case reaches the rear of the gun 6-17. On an M61A1 automatic gun, the bolt-locking block   is   forced   upward   by   which   of   the following components? 1. The buffer 2. The electrical solenoid 3. The coil springs 4. The leaf springs 6-18. A drum unit assembly consists of the drum unit and what other major parts? 1. The  entrance  unit,  scoop  disk,  and  exit cover 2. The entrance cover, transfer unit, and exit cover 3. The entrance unit, scoop disk, and exit unit 4. The  entrance  cover,  scoop  disk,  and  exit cover 6-19. In a drum unit, ammunition rounds are moved along   the   length   of   the   partitions   by   what means? 1. The entrance cover 2. The scoop disk 3. The rotation of the outer drum 4. The rotation of the double-lead helix 6-20. What  component(s)  control(s)  the  position  of the rounds as they are passed from the entrance cover to the scoop disk? 1. The retainer partitions 2. The inner drum helix 3. The entrance unit 4. The scoop disk extensions 6-21. What component provides rotating support for an inner drum helix? 1. An exit cover 2. A scoop disk 3. An entrance cover 4. An inner drum adapter 6-22. What component contains a last-round switch? 1. The entrance unit 2. The entrance cover 3. The exit unit 4. The exit cover 6-23. What  component  prevents  expended  rounds from being fed into the M61A1 automatic gun? 1. The first-round switch 2. The last-round switch 3. The projectile sensor 4. The empty case sensor 28