Slashdot Mirror


New Tech Puts the Brakes On Bullets Fired From Police Sidearms

Zothecula writes: Police officers are trained to shoot for the center of mass, not necessarily to kill, but to stop – although the end result can often be one and the same. "The Alternative" is designed to give officers a less lethal option in the form of a clip-on "air bag" for semiautomatic pistols that reduces the velocity of a standard round to make it less lethal. At the front of the bright orange carrier is a hollow sphere made of a proprietary alloy that catches the bullet and firmly embeds it as it leaves the barrel. The ball and bullet fuse, slowing the round by 80 percent. At this speed, the ball-encased round is less likely to penetrate flesh, but it will transfer enough kinetic energy across a wide surface to knock a suspect down with less chance of a lethal outcome.

15 of 369 comments (clear)

  1. Bullets don't knock people down by SpaceManFlip · · Score: 4, Informative

    This is stupid because a normal bullet doesn't even have the kinetic energy to knock over a person. That is all Hollywood make-believe.
    There's a whole series of tests done on Mythbusters that debunked the concept.
    So these bullets are going EVEN SLOWER than normal ones, and it's supposed to "knock down" a person?
    Think about this: a typical 9mm round will be 115 grains or 124 grains in weight. One grain is 1/7000 of a pound. We're talking about a projectile going in the ballpark of 1000 fps that weighs only about 0.0177 pounds for the 124 grain bullet. There simply is no knock-down potential.

    Now, on the other hand, if you are seriously injured by one of those projectiles, you'll probably fall over in pain. Or you might also just fall over dead.

    1. Re:Bullets don't knock people down by jIyajbe · · Score: 4, Insightful

      (Trigger warning: Physics teacher here!)

      Actually, momentum is NOT conserved for the *shooter*. He is bracing himself against something (his feet on the ground, usually), so there is an external force acting on him. Thus, this particular argument fails.

      For the victim, if he is shot unawares (so he doesn't brace himself), then conservation of momentum *does* apply. I calculate that he will experience a force to his chest of about 35 newtons (~8 pounds). That's not much, and won't accelerate him much.

      However--it may well knock him down. The reason is, the force to his chest will cause a torque on him, which will cause him to rotate down to the ground. If we assume he rotates about his feet, and treat him as a solid cylinder (reasonable approximation) then I get an angular acceleration of about 0.4 radians per second per second (22 degrees per second per second).

      That only lasts while the bullet is in contact with him, of course; after that, the victim has a gravitational torque on him, with a corresponding angular acceleration (I estimate) of 9 rad/s/s.

      If someone wants to check my work, I'll supply the numbers and things I used. I might well have made a mistake or missed something.

      --
      "Don't blame the log for the fire." --Andrew Ratshin
  2. Yet another Gizmag article on a hair brained idea by Obscene_CNN · · Score: 4, Insightful

    Looks like some idiot an Gizmag was talked into doing an article by some hair brained inventor again. Neither party understands physics so they both think its great. As mentioned a few times here by others before me that firing a bullet into another ball isn't going to increase its knock down power (Conservation of momentum). The stupidity from there grows by training a law enforcement officer to use the gun as a first resort instead of a last one. Also for when lethal force is called for it means that the officer will have one less effective bullet and their follow up shots will be done with them dealing with the recoil from their first useless shot. Bad idea all around!

    --
    I don't want to do a sig now
  3. Re:How about take away their guns. by x0ra · · Score: 5, Insightful

    How do you plan to disarm criminals ? The gun, ammo, and knowledge to build them is out there. If an Afghan can build an AK in a cave with nothing but hand-tools, what do you think someone in the US can do with access to milling machine, lathe, and 3D printer ?

  4. Rubber Bullets by Roger+W+Moore · · Score: 5, Insightful

    Why not just use rubber bullets or baton rounds? The technology has been around since the 70s and you are not limited to one less-lethal shot. In fact rubber bullets seem like a far better idea - with this solution what happens if the first shot misses?

  5. The problem with "non-lethal" weapons by JustAnotherOldGuy · · Score: 4, Insightful

    The problem with "non-lethal" weapons is that when given to police, they tend to use them more often and with less provocation than with a firearm.

    Look at how taser-happy the police have become- FFS, they'll tase you for just standing nearby watching what they're doing.

    When I was growing up the police were much more reasonable and much less likely to go ballistic/aggressive when questioned...now if you dare to question them, out comes the pepper spray, baton, and taser. If that doesn't immediately make you "comply" (i.e. go away, stop watching, stop filming, whatever) out comes the gun and handcuffs.

    I've seen it myself. Today's police officer has a gun (often 2 guns), a baton, a knife, a taser, pepper spray, steel-toed boots, a ballistic vest and a radio. And yet police today are the biggest pussies I've ever seen. They dress like extras from RoboCop and yet they're scared shitless and feel "threatened" by a teenager wearing a t-shirt and shorts. When did cops turn into such pants-wetting pussies? When did they become such chicken-shit cowards?

    --
    Just cruising through this digital world at 33 1/3 rpm...
    1. Re:The problem with "non-lethal" weapons by PopeRatzo · · Score: 4, Insightful

      I've seen it myself. Today's police officer has a gun (often 2 guns), a baton, a knife, a taser, pepper spray, steel-toed boots, a ballistic vest and a radio. And yet police today are the biggest pussies I've ever seen. They dress like extras from RoboCop and yet they're scared shitless and feel "threatened" by a teenager wearing a t-shirt and shorts. When did cops turn into such pants-wetting pussies? When did they become such chicken-shit cowards?

      I believe it has something to do with the end of the draft.

      When were younger, the police were made up mainly of people who had been in the military. But they had been drafted into the military so the chances were good that a lot of them were just regular people who needed a job and wanted to serve and protect. Today, an even higher percentage of police are ex-military, but these jackoffs volunteered to go to some third-world country to massacre brown people. They probably got turned down by the Blackwater/Xe/Academi type outfits where they could make some real money menacing people, and instead ended up on local police forces, thinking of themselves as some kind of liberating/occupying force in residential neighborhoods. They don't think of serving the public as much as they do fighting the public

      There were always bad/brutal cops, but today, it's de rigueur to be bad/brutal.

      Having said all that, I live near the Chicago Police Academy, and they're starting to get higher-quality recruits. But the bad/brutal jackoffs are now brass, trained in the First Gulf War, and think every policing issue requires the use of armored vehicles and snipers. So that's how they get trained. I'm hoping the next generation is a little better.

      --
      You are welcome on my lawn.
  6. Re:How about take away their guns. by narcc · · Score: 4, Funny

    Check to see if he's white?

    Isn't that standard police procedure for identifying law-abiding citizens amidst criminals?

  7. Re:How about take away their guns. by hodagacz · · Score: 5, Interesting

    If they're brandishing they're not a good guy. Brandishing means to draw and display to give the impression of intent to use.

  8. Re:Newtonian physics by duckintheface · · Score: 4, Interesting

    If you have fired a pistol, you know that the "kick" of the gun is not even close to what would be required to knock you down. And of course people are shot in the chest all the time without being knocked down. But in the case described in the article, the bullet has even less kinetic energy because it has been intentionally slowed down by the plastic cap. If it has slowed by 80% as stated, there is no chance that the bullet could knock someone down.

    --
    "He took a duck in the face at 250 knots." -- William Gibson, Pattern Recognition
  9. Re:Newtonian physics by LynnwoodRooster · · Score: 4, Interesting

    A 115 grain (7.5 gram) 9mm bullet from a Glock G17 has around 370 m/sec of velocity. Take that down to 75 m/sec and you're around 21J of energy. That's about the energy you'll receive from a punch by an 8 year old boy. If that knocks you over, the police probably could have caught you just by a brisk walk as you were trying to escape on your walker.

    --
    Browsing at +1 - no ACs, I ignore their posts. So refreshing!
  10. Re:Newtonian physics by Firethorn · · Score: 4, Informative

    Are you accounting for the extra mass of the airbag device? Going by physics:
    It's momentum is 370*7.5 = 2775 gm/s
    2775/75 m/s = 37 grams for "the alternative" + bullet, meaning the sphere should weigh ~30 grams.

    37 grams@75m/s = 208 J

    BTW, when I calc your figure I come up with 42 J, not 21.
    7.5 grains* (75 m/s)^2 = 42.2 J

    By the way, I looked up Bean bag rounds.
    40 grams@70-90 m/s, which impacts ~6cm^2.

    Seems roughly equivalent to me. The ball is right in that velocity zone, a little light by my estimate, but it's likely to impact a slightly smaller area. Might just work.

    --
    I don't read AC A human right
  11. Re: Newtonian physics by jafiwam · · Score: 5, Insightful

    Getting confused about which gun shaped handle is in the hand is common place enough as it is. Many (dozens) of people have been shot with real bullets when the officer intended to be firing a Tazer. This is the reason many Tazer holsters are cross-draw now and not just in a second holster on the strong side.

    This thing, is going to be fired from the SAME weapon and without a lot besides mental training between it, and real bullets. Follow up shots will come right after when the officer did not intend them. Guaranteed. If it gets used, it will get confused, and people will die over it.

    This stupid little tool isn't going to work, it's a minor pain compliance tool attached to a "gonna wipe your ass out" tool where things shouldn't be mixed. It's LESS painful and LESS damaging than an asp or night stick.

    The only real benefit is this thing can be just clipped on and takes up less space on the belt, or could just sit in a holder on the dash or something.

    The dumbass inventor drags it out and pays to have a big marketing stir about once a year, or whenever police have shot someone and it made a bunch of news.

  12. Re: How about take away their guns. by jafiwam · · Score: 5, Insightful

    15 years ago that was every boy. Now you have to be some kind of troubled youth to enjoy killing can with BBs.

    I went all over with a BB gun (rifle and pistols) and NEVER ONCE pointed at people in order to get a kick out of scaring them, menacing them or anything like that. Also, when the cops showed up (for whatever reason, never had the neighbors complain about what we were doing with BB guns) we stopped what we were doing, answered questions politely and complied every time.

    The difference is not the gun or the BB gun or the airsoft gun. It's the culture, mindeset, intent, and parenting of the person holding it that counts.

    Getting shot or not is mostly in the control of the shootee, the shooter is not the driving force (other than being in a profession that is the force part of "authorized force by the state."

  13. Re: How about take away their guns. by DigiShaman · · Score: 4, Insightful

    The difference is not the gun or the BB gun or the airsoft gun. It's the culture, mindeset, intent, and parenting of the person holding it that counts.

    Succinctly well said. And I'll add that parents and the rest of society needs to instill a cultural understanding that we don't live in our own little worlds, but one in which we all share the resulting consequences of our actions. For example, no one would jump out of a plane without a parachute unless they're suicidal, right?! So why should anyone think waving a gun around in public with the intent to scare is a good idea?

    --
    Life is not for the lazy.