Yes , but the biggest difference is the selective fire . GAU 22 A can fire 1 round , 4 rounds , 132 rounds , 180 rounds . however many rounds you want to shoot , you can select it , and when you pull the trigger , only that many rounds fire . GAU 8 is by trigger duration only . What that means is , if there ' s a Toyota truck technical , I honestly only need 15 rounds to take it out . I can fire just 15 rounds on it , and score the hit . I don ' t need to do a 150 round burst like GAU 8 typically does . This is especially important in danger close missions , where that technical may be close to friendlies , and 150 rounds with a CEP of 40 meters , could very well lead to a blue on blue incident , where you ' ve essentially entirely eliminated the potential for a blue on blue with a limited burst fire .