We recently saw an increase in the spread of 6.5mm gatling-gun type weapons, seen on the Ghosthawk, Huron, and Orca. This makes it much easier to hit targets while either firing at odd angles (such as in the case of the door gunners in the Ghosthawk or Huron) and while firing using the advanced flight model (to compensate for the added difficulty of aiming the weapons).
However, the M134 7.62 miniguns mounted on the Pawnee and Hellcat continue to exhibit laser-like precision. This makes killing targets at anything besides maximum range difficult, as the lines of fire from the guns sweep all around the target without hitting them unless a lucky shot is scored. 7.62 rounds should by all means remain more accurate than 6.5mm rounds, but they need their own boost in bullet spread to make hitting targets easier when using the advanced flight model.