weapon range

Maximum effective weapons range is 500, though the display only shows up to 300. These values are hard-coded.

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in other wprds, finda range you like and copy paste and edit the weapon, making a new one with the same range!, its what i do anyway.

But then, whats this?

//---------------------------------------------------------------------------------------
Weapons Range Short := 30.0
Weapons Range Medium := 60.0
Weapons Range Long := 1000.0

-from settings.txt

Just try creating any weapon with range over 300, in my mod it was working well.

P.S. I wonder, for what you need this?
1) If for direct fire weapon weapon, you can have problems with accurancy. As i remember my rail guns were working well at distance 350, i used "Weapon Space At Range Distance Increment:= 0.4".
But any formulas i used was not able to block weapon at short range.
2) If for missiles, i just created missile unit type with it's own warheads and engines from fighters, -95% cost modifier, don't use suplies etc, even planets without space yards were able to build few hundreds of them per turn. It made range unlimited (also i made 0 movement points and combat speed 30-120, depending on size, to make it cheaper i used only one engine).