low accuracy weapons like machineguns and miniguns start to be useful at around half of their maximum range. At max range even full bursts go in space. Other problem with them is that they have bullet speed (unlike lasers and PPCs) so when the ship have any angular velocity to you more bullets will be wasted. Laser type weapons deliver damage instantly (of course if they hit). Other great advantage of laser is that the beam stays for around half a second. If anything cross the beam during that time gets damaged. Half a second may sounds short but let me give an example I saw: Astarte fired with two muskets and missed both but during that time two fighters crossed the beams and they instantly vaporized
. I wanted to hit at least one fighter but killed two
.