Many of the gun myths perpetuated by Hollywood suggest that experts using firearms can make their choice of weapon do magical things out of sheer skill and gumption. Then there's this one, which is more to do with the sort of things that happen when you're at the other end of the weapon. It looks cool when a character literally blows an enemy away. Not only do they riddle them with bullets, but the bullet fire causes the bad guys to be thrown backwards like a rag doll, their bodies going limp as they soar through the air from the velocity of the bullet. Absolute nonsense. That's just not how physics work. Bullets possess relatively little momentum due to their small size, especially when compared to people, which means that it's simply impossible for a bullet shot to send you even stumbling backwards.