[Tempest]

I'm making a mod with some seriously long-range beam weapons. And, try as I might, I can't seem to be able to do anything that keeps the AI from sniping me, with deadly precision, from many kilometers away. Is there any way to make the AI more...human...in their (in)ability to hit things at such range? I've given the AI ludicrously low accuracy values that work as expected in a dogfight, but they are just too good at long range.

[Wanderer]

Beam weapons are exempt from normal targeting rules - with the 'sort-of' exception of mounting type 4 beams on multipart turrets.

You can change the beam weapon accuracy values in the weapons.tbl beaminfo section. That's about all you can do. Bad thing is that then AI will target poorly the larger and closer targets as well.

[caibrenden]

Beam sniping 

Anyway that seems like a ridiculous idea to have it called a beam.
Call it a Pulse Cannon or something
and

Beam weapons are exempt from normal targeting rules - with the 'sort-of' exception of mounting type 4 beams on multipart turrets.

You can change the beam weapon accuracy values in the weapons.tbl beaminfo section. That's about all you can do. Bad thing is that then AI will target poorly the larger and closer targets as well.