Impossible to escape

The shooter was on point with the imported AR-15 rifle in his hands, he was confident his aim to the wheel of the car wouldn't miss and the wheel would burst at the touch of the bullet. 

If the driver controls the car, he could shoot the lady when they alight. If the driver fails to keep the car on the road, the car will topple aside. His second bullet would burn down the car.

His plan was set and all prepared. The fat man started the countdown to the shooter which was also the distance from them to the car.

"500 meters away, 5… 4… 3… 2… 1, Shoot." He commanded in confidence that they could return the gang with glory.

He was still holding the binocular over his eyes to witness the result of their first fire so that he could instruct if the second bullet was required.

One second...

Two seconds...

Three seconds passed but the car was moving fluidly without disturbance. 

Wait, the bullet sound?