I have a 4-20 atacr on mine. Good balance of mag and size. I guess it depends what your use is. Mine is hunting so I like 4 for low light. But wouldn’t hesitate to run my 7-35 atacr on it either if target shooting was my primary use. Especially longer distance or if I planned to use another barrel for 1000+ yard shootingWhat do you fellas say is the ideal mag range for a 20” 308 AT? 3-18, 5-30, 6-36?