I have been contemplating potential “less lethal weapons” for a story I am writing. I found Cecil’s article, “The Physics of Punching Someone in the Face”, and it got me wondering about a possible weapon. Consider a weapon designed to fire a blunt arrow or rod with a hollow shaft; on impact, a weight inside would slide forward to, theoretically, increase the impact on the target. Questions: 1) Would the weight actually increase the “punching force” / psi? 2) Could such a weapon be used in a compressed air gun aka tranquilizer-type gun? 3) Could such a weapon be calibrated to provide a consistent psi, assuming it was fired from the same distance each time? 4) In Cecil’s article, he discussed that martial arts, “Short-range power punches averaged 178 pounds.” How many psi would be “effective” against an average person? i.e., providing enough of a blow / impact that a person would yield after one or more blows. 5) Note that this is similar in concept to shotguns firing out specialized beanbag rounds, but these have caused blindness, death, etc. Could this concept be designed to be less lethal and more effective than bean bag rounds? Perhaps in combination with a Variable Velocity Weapon? 6) Similar to Q1, is there any advantage to having the weight in the shaft with regard to changing up the speed, force, psi, etc. and making it less lethal?
How is the proposed weapon any different from just firing the weight without the hollow arrow shaft? When you fire the tube+weight system, you spend energy to give the tube and weight some velocity. In flight, the tube and weight are travelling at the same speed. Once they hit the target, the tube slows down first because it hits the target first; the weight continues forward – at the same speed it was going originally – until it also hits the target. There’s no “extra impact” – assuming the hollow tube is fairly light, you could have just fired the weighted part to get the same effect.
Thanks SP. That’s what I suspected. I came up with the question from retractable point darts, which supposedly stick in the dart board better.
Anyone have other new ideas for “less lethal weapons” ?
What I am picturing is sort of a “negative image” version of a mechanics “slap-hammer” such as those used in auto-body work. If you could somehow control the weight to come forward at impact and not before or much after, yes - impact would be increased. For stability a bolt in a crossbow would be a better bet than a full length arrow.
Based on experience with arrows using blunt points (both mushroom shaped as well as conical) I would call a bean-bag nightstick far less potentially lethal. And a blunt from the average crossbow? I wouldn’t want in front of it even in protective clothing and gear.
How about using a high-power paint-ball gun with a heavy liquid center. If you want to stick to muscle powered weapons, though, your best bet is a sling or slingshot with frangible ammunition (e.g. chalk, limestone, dried unfired clay,)
The problem with any form of blunt object is Newtonian physics. If the forward motion is strong enough to drop a human being to the ground, it will by necessity impart the same amount of force to the shooter. The sliding weight you describe will not increase the force of the impact. If anything, a two-stage impact would divide the mass of the projectile and you’d end up with two lighter strikes rather than one heavy one. Further, the tip would need enough surface area to avoid penetrating the body, which would reduce the aerodynamic performance.
I would shoot an arrow with an electric taser on the end, and the batteries in the shaft.
You’re making up a story, why not make up the physics of your weapon? Who’s going to care if you don’t allow for friction as the weight slides forward in the hollow tube? Just say that’s how it works - it will give peoole something to talk about here or on Amazon.
Or a big green boxing glove!
The impact is not really increased or focused with a slide hammer. It’s the same impact as with a hammer, just on a track, so you can pull instead of push. Once your missile is on the way, you may as well have a solid slug.
For fiction, maybe have a projectile that has a contact sensor that sets off an expanding slug. So, once it reaches the target, the slug expands into a soft-ish blob that knocks the wind out of the guy. You get good ballistics because it stays compact in flight, and gets very soft on contact to reduce injury.
How about a gun like the Nerf Vortex http://www.buy.com/prod/dd-nerf-vortex-vigilon/235734426.html?listingId=233302337 that shoots weighted washers instead of foam discs?
A net gun.
I hear you, Frank, but I’m trying to keep my stories as realistic as possible. There’s a lot of Star Wars type stuff around, which I love, but we need a lot more “hard” sci-fi.
Thanks for all the replies everyone. The paintball gun led to the Variable Velocity Rifle I mentioned. Check it out. Pretty wild. I was thinking that a laser w/ computer could possibly estimate the size/mass of the target, based on width and height, and adjust the velocity according to that, as well as distance.
I was looking at some videos on net guns. They’re cool, but would they be effective against an armed opponent, or several armed opponents? Seems like reloading would be challenging.
The paint ball gun is a good idea. Just make sure to put the paint balls in the freezer for at least an hour first.
If the story is fiction, or science-fiction, imagine a cocoon-like bullet that expands into a filiment net when fired. With six shots.
The US DOD has an office for this category of weaponry, which isn’t too surprising.
http://jnlwp.defense.gov/resources/usanlw_info.html
That website isn’t very useful, but this one is more intriguing: 6 | Cracked.com
Go to page 2 and you will find “Taser XREP (aka Electrified Shotgun Shells)”. Based upon the accompanying photo, you are not required to wear a purple mask to use this weapon.