Intuitor Insultingly Stupid Movie Physics:
"First, let us point out that the thirty-round magazine in a Mac 10 will be expended in a mere 1.8 seconds of sustained fire! If our shooter blazes away steadily for a total of only 3 minutes, his or her Mac 10 will spit out around 3000 chunks of lead at roughly 15 grams a piece. This amounts to 45 kilograms or a little less than 100 pounds of lead. And that doesn't account for the weight of the 3000 cartridge cases or 100 empty magazines scattered on the ground.
Second, bullets are, after all, propelled by some very hot gasses which exert high pressures that create high stresses in gun parts. A firearm can withstand the high pressures and stresses only if the blasts of high temperature gasses don't happen too many times before the firearm has time to cool off. Running 3000 of these temperature cycles back-to-back would turn a light weight submachine gun, like a Mac 10, into a red hot piece of scrap metal, that is, if it even lasted for 3000 rounds."
Here is an essential website. Not only do they counter stupid movie mistakes, they use the laws and formulas of physics to do it. Also included is a section on why a shotgun blast will not hurl a human target backwards 30 feet through the nearest plate-glass window.
