Something else I caught in the book was him talking about distance when firing. He would keep checking the pipper and the distance to his chosen target and that anything over 300 yards was "out of range." He preferred to be inside 250 yards. This was apparently part of their training, and how convergences were set as a regular course for all of them, not just him in particular.
Even though gunnery is ( I assume) much easier here in a game than it was in real life, it's funny to me that this is the same general range many of us find works best here as well. Under 400 yards down to as close as you can get without running into them.