Been reading up on the Combat rules and thought I'd better check something:
Short Range (+10 BS) is between two metres and 25% of the weapon's listed range (page 249).
Long Range (-10 BS) is twice the weapon's listed range or greater, with Extreme Range (-20 BS) being anything over three times the weapon's listed range.
So a Standard Attack for a Godwyn-patter Bolter is taking a shot at anything between 50 and 200 metres away from the shooting Marine.
I do have that right, right?
If so: Wow! You can have HUGE battles before having to worry about negatives to hit.
Actually, it seems like it'd give a Marine half a chance against a Genestealer. Even a Running one would still need two turns to close with its intended target before it could Charge.