Quote Originally Posted by DTruck View Post
That logic would point to the AMOUNT of gas, not the timing of the initial gas pulse. With that said, I'm tending to agree with you that a light buffer, a light spring, and an opened port for more gas can overcome the slow timing of the carbine gas, to a degree - Enough to cycle consistently by pushing the action "faster".
The amount of gas is more of the issue with subs, because there isn't much powder in the round. By the time you get down to the 7 inch gas block with minimal gas to begin with, there isn't enough gas, and therefore enough pressure, to keep the bolt cycling properly. An open port may decrease gas pressure, which isn't going to help, as there's a fine line there between keeping volume adequate and enough pressure.