The numbers of the sight represents 100's of yards, so when shooting, aiming with the "12" line, the round will go 1200 yards (1.2K).
To make tanking more challenging all icons were removed for ground to ground purpose, so the only way you can really get to know their range is to either fire a shot and see how far it was off, or have maybe a friendly plane fly over the tank, so you can see HIS range and thereby also the tank's.
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Snefens
-=Aces High Training Corps=-