[blaser-waffle]

They're not going to be able to guess that, or be especially concerned with the range -- if bullets are coming by they're getting down or hauling ass.

You aim for the center of mass -- roughly at the heart. A bullet, thusly aimed, that drops slightly short can still hit someone in the leg or lower abdomen. Or it'll hit the ground and kick up dirt, be more visible.

A fixed height for each tick mark also means you can use the enemy high to roughly calculate distance.