I've got a few Frontline Pulse Laser Turrets, and I've noticed that the displayed range arc, and the range at which they start firing, doesn't match the range where they start dealing damage. So if there are one or more biters at the edge of the Pulse Lasers' range, the lasers will start firing at them, but not actually deal any damage (and thus waste a lot of power). For a minute, I thought the lasers were completely broken and not dealing any damage, but then I realized that they did start applying damage once the Biters got a few steps closer.
I didn't measure the exact gap between effective-range-vs-firing-range, but just eyeballing it, it looks like the lasers start firing at things about 5 tiles beyond where they actually deal damage.
I know very little about Factorio modding, but I had a hunch that this might be related to the turret ammo_type action_delivery having a max_length of 35, rather than the turret's actual range of 40; and when I went in to the mod files and changed that max_length to 40, the laser started behaving as I would expect (every shot deals damage, at full range). I have a further hunch this was probably an incomplete change from version 7.1.0, which notes that Frontline Pulse Laser range was buffed from 35 to 40.
