Laser range finding scopes would work!

[Aculaud 0]

I'v been thinking of a USMC M-40A1 or A3 with a laser range finding scope for OFP. It could use the mil-dot optics system, and be zeroed at about 150 meters. Then, the laser range finder would tell you how far away the target is, and hence, how much range to compensate for.

Notice how, when you command troops in a squad and select one of them, you can hold the cursor over any place on land, and it will tell you how far away in meters that place is. The scope could display something similar.