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You Can’t Take a Bullet for Someone Hollywood-Style, Because Physics

The views expressed are those of the author and are not necessarily those of Scientific American.


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No matter how many times you’ve seen the movies and the TV shows that have a protagonist leaping in the path of a bullet, physics forbids such sacrifice. Because of a bullet’s radical speed, you can’t jump in front of it, but you could get in its way. It’s not as dramatic, but it does save lives. The Secret Service saved a president that way.

Bullets move fast enough to create their own shockwaves, like a speedboat on the water.

Bullets are fast—even a 9-millimeter handgun launches lead at Mach 1. And the bigger the bullet gets, the more grains of gunpowder it carries, the faster it goes. Modern rifles can fling the small pieces of metal at half the velocity needed to escape the gravitational pull of the Moon. Our weapons are so fast, in fact, that you couldn’t get in front of a bullet even if you saw it coming.

Thanks to due diligence done by the Discovery Channel’s Mythbusters, we already have a sense of the range at which moving in response to a bullet is possible. In their testing, Adam and Jaime established a “kill zone”—the distance at which you could not dodge a bullet given human reaction time.

But to dodge (or jump in front of) a bullet in the first place, you have to see it coming. The Mythbusters estimated that you’d have to witness a bullet fired from over three football fields away in order to have enough time to dodge it. Any would-be hero with a reaction time longer than Jamie’s would need to see the bullet from further away—something that subsequent testing deemed impossible.

Hollywood makes it seem like average Joes and Janes can suddenly make that superhuman leap in front of lead for two reasons—speed and sight. But physics has no sympathy for your heroic aspirations. Optics doesn’t either. You are not that fast. You can’t see a bullet fired from that far away. If the testing that the Mythbusters did holds up, there is no way you could see a muzzle flash from much further than a hundred meters or so away. Point-blank shooters fire too close for you to even blink, and snipers worth their salt use bullets that suppress muzzle flash. Brightly flashing guns make for good shows and movies, but there is no such “take a bullet” cue in real life.

But you could stand in front of a bullet in anticipation of being a hero. It’s happened before.

McCarthy (far right) few eye-blinks before the attempted assassination of Reagan (waving). Left, in white trenchcoat, Jerry Parr, who pushed the President, body-sheltered by McCarty, into the car.

Outside of the Washington Hilton on March 30, 1981, then president Ronald Regan enters his car amid the crowd gathered to hear his speech. John Hinckley, Jr emerges not with admiration but with bullets. Shots ring out. In a motion burned into reflex, Secret Service agent Tim McCarthy shifted from his alert position into one like a baseball catcher in front of the president. One of the next shots stuck McCarthy directly in the stomach. He then defined what it was to “take a bullet.” He made a full recovery.

The Secret Service, whose agents are probably at the heart of the trope to dive in front of bullets in TV shows and movies, never stopped a bullet that way. Agent McCarthy indeed took a bullet for someone, but only after a few shots rung out and only acting as a human shield. That’s what taking a bullet really looks like. Heroes are meat shields, not stuntmen.

Image Credits: Supersonic Bullet Shadowgraph via NASA/JPL

Screengrab from Discovery Channel’s Mythbusters

Assassination attempt photo uploaded to Wikipedia from the Ronald Regan Library Archives

Kyle Hill About the Author: Kyle Hill is a freelance science writer and communicator who specializes in finding the secret science in your favorite fandom. Follow on Twitter @Sci_Phile.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. tuned 12:03 pm 11/19/2013

    Tekkies and shooters have always known this.
    This article is for the “lay” people.
    Caveat: the following is simple fact only.
    A high velocity bullet or shotgun load hitting between the eyes is the most merciful form of death, just messier maybe.
    It has long been known they travel faster than the nerve impulses even. It is not seen, heard, nor felt before the brain is “gone”. No chance of a mistake by chemical means, or immunity/resistance.

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  2. 2. Looie 12:09 pm 11/19/2013

    This error bothers me less than the one where somebody struck by a bullet is flung through the air and lands five feet away — not realizing that by conservation of momentum that could only happen if the person firing the gun is thrown backward at least as strongly.

    Bill Skaggs

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  3. 3. winnre 1:38 pm 11/19/2013

    “And the bigger the bullet gets, the more grains of gunpowder it carries, the faster it goes.” Um, bullets don’t carry gunpowder, the gunpowder projects the bullet.

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  4. 4. Mirzero 2:40 pm 11/19/2013

    I think the trope usually involves anticipating the shot before it’s happened, and diving into the line of fire (not dissimilar to what Mr. McCarthy did). Actually seeing the shot then diving is, as you describe, ridiculous.

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  5. 5. CharlesRKIss 7:05 pm 11/19/2013

    Isn’t the horizontal axis of the graph supposed to read: “DISTANCE(YARDSx100)” ??

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  6. 6. lorddix 1:14 pm 11/21/2013

    “snipers worth their salt use bullets that suppress muzzle flash” As far as I know there are no bullets that suppress the muzzle flash which is a result of the burning gunpowder, what suppresses the muzzle flash is an extension at the end of a rifles barrel called a flash suppressor, which redirects the burning gunpowder residue exiting the barrel behind the bullet in such a way that makes it less visible.

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  7. 7. jstahle 5:16 pm 11/22/2013

    Jeeeez!
    One does not react to the bullet, but to the sight of the gun.

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  8. 8. MrGman 6:43 am 11/30/2013

    What they were trying to say is by the time you see the muzzle flash the bullet has already hit you. The flash suppressor, is used so anyone who survived the first shot has a harder time pinpointing where the shot came from.

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  9. 9. vmaldia 12:00 pm 11/30/2013

    \\“snipers worth their salt use bullets that suppress muzzle flash” As far as I know there are no bullets that suppress the muzzle flash which is a result of the burning gunpowder, what suppresses the muzzle flash is an extension at the end of a rifles barrel called a flash suppressor, which redirects the burning gunpowder residue exiting the barrel behind the bullet in such a way that makes it less visible.\\

    Also faster burning gunpowder tends to burn up before the bullet leaves the barrel. Slower burning gunpowder means some unburned grains leave the barrel after the bullet has left, and these grains then start to burn outside the barrel, causing muzzle flash. so faster burning powder can reduce flash

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