system
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human
[Warhammer 40k / battlefleet gothic]Weapons ranges and ship engagement range.

I am a solider of the Astra Mili..... Imperial Guard. I love the ships of the Imperial Navy from the smallest of the Cobra Destroyer to the might of the Retribution Class Battleship. Praise the Adeptus Mechanicus and their work. I always wondered what the weapon ranges of weapons like the Lances, Macrocannons, and Torpedoes. What about our enemy like the Tyranids, Eldar, Orks, or the Necrons. What their weapons like and how do we unleash the fury of the emperor upon his enemy. I have looked high and low to find any relevant information on the matter. To any Imperial Navy or Adeptus Mechanicus that can give relevant information, what it like to fight of our enemy. Thanks and now the commissar said that we're on the move again. May the hand of the Emperor guide all.



**+++Serve the Emperor today, tomorrow you may be dead+++**
gpt
From a fluff perspective: Torpedos can be fired from the edges of a system, we saw that in *Pharos* (came in at just under lightspeed, which we know is achievable with regular engine thrust according to *Dark Hunters: Umbra Sumus* - in fact, regular engine thrust can be used for FTL travel across a sector, granted it's barely a few multiples of c). Macrocannons tend towards generally being closer range than Lances, which go up into the tens of thousands of km, and Nova Cannons go into the high tens of thousands to low hundreds of thousands of km. Although as with everything in 40k, you'll also have situations where primary lances are reaching into 500,000 km (as in *Salvation's Reach*), sooo....it depends? As a soldier all you have to worry about are two things: 1) Gellar fields failing or 2) disappearing in a bright flash of light as your transport ship gets blown to smithereens by something you couldn't even see if you looked out a window.      

10,000 km ish is pretty close range for 40k ships going from the BFG rulebooks, although that tends towards being a baseline rather than anything else, because it's normalized for a game and a reasonably sized board.