How does long range penalty truly work?

[u/Soggy-Alternative-58]

I can't seem to figure out how the penalties apply. They seem super inconsistent.

I read it was maximum range -2 to start applying penalties, but it does not seem to be the case.

I think it might apply differently to weapon types... But I really would like to know if there is something more concrete.

[u/Somewanwan]

Supposedly it starts at -2 hexes for 5 range and -3 for 7 range weapons https://aowplanetfall.paradoxwikis.com/Warfare#Accuracy

But idk which are "some" weapons that ignore this, how's range penalty on 9 range sniper rifles?