So what does that bullet do?

shootingcars
So you pulled the trigger, your front sight was centered right on the guy’s chest as he sat behind the steering wheel . . . but you missed. So where did that bullet go?
When shooting over a car hood, you don’t lean over the top of the hood and rest on it, like Starsky and Hutch. You backed away from it, because incoming fire might strike the engine block, which slopes upward, then hit and deflect off the engine up through the hood, throwing lead and engine frag into your face, arms, and chest. That’s part of something called terminal ballistics—what a bullet does when it hits something.

When a bullet hits a wall, it doesn’t necessarily ricochet off at an angle opposite the one it came in on, like a cue ball on a pool table. It can actually hug the surface of the wall or ground for a while and travel along that surface. The principle didn’t apply just to vertical surfaces, either—it applies it to shooting under cars as well.

If the enemy was using a vehicle for cover, you can fire at the concrete or asphalt in front of the car, about where the shadow line would be on the ground at mid-day. Your incoming rounds chew underneath, sending bullet, asphalt, and gravel into the legs and ankles of the enemy shooters. Then do it again to send the same thing back into their bodies after they fell from having their legs chewed up.
shootingcars
Now back to that problem with the bullet and the windshield. If you’re facing a vehicle and shot into the windshield with your 9 mm pistol, aiming at the chest of the guy in the front seat, the bullet would actually hit him somewhere in the lower abdomen, depending on how far away you were.

The reason is that the underside of the cone-shaped bullet would make first contact with the glass, dragging the bullet down slightly. So, to hit a target sitting in a car in the chest when you’re shooting at him while facing his car, you aim at his face. That worked for nearly all pistol rounds. If you’re shooting a rifle like an M4, whose bullets travels a lot faster, the bullet won’t drop that much, and it was basically point of aim, point of impact—where you aimed was where he’d get hit.