Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
These statements have not been evaluated by the Food and Drug Administration.

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



enhancing the m16/m4

deepening a cannelure to enhance the m16/m4
  (+4, -8)
(+4, -8)
  [vote for,

I. Introduction

the 5.56 bullet was derived from varmint ammunition, ammo designed for animals the size of rats and squirrels. But it was adopted for use against humans, which are much much larger animals

this is why it works against humans. all rifle bullets are long and slim with the center of gravity near the base. the spin imparted to the bullet stabilized the bullet in a point first direction. but the spin is only enough to stabilize a bullet in air. in thicker mediums like flesh the spin isnt enough and the bullet likes to yaw until the base is going first. when it is going sideways it makes a bigger hole.

All rifle bullets do this. what makes the 5.56 different is that it can fragment when it goes sideways. hold a piece of paper and stab it with someting pointed, you get a small hole. get a piece of paper and stab it while being stretched, you get a big tear. same thing with flesh. when the temporary cavity and tension of the flesh is at its biggest (when the bullet is sideways) the 5.56 fragments and the small fragments hit the tense flesh, the flesh tears, resulting in a bigger hole. The faster your bullet the more chance it can fragment, thats why the lower velocity m4 carbines do poorly at long ranges.

How come only the 5.56 fragments? because it has a cannelure. a cannelure is a notch cut in the jacket of the bullet so the lips of the cartrige case can grip it better. the notch means the jacket is thinner there and it may be weak enough to fragment.

The ak74 and the h&k mp7 and the p90 have bullets that are designed to yaw early so the biggest hole is more or less located inside your body. if it yaws too late, the bullet might have exited your body before it can yaw. but all of these dont fragment.

II. The Idea

so a problem with the m4 carbine is that the bullet is much slower than the old long barrel m16 so there is more chance that the bullet's speed will not be enough to fragment and/or the minimum range for fragmentation is much shorter. for other rifle calibers, normal FMJ ammo doesnt fragment

for the 5.56 i propose that you either deepen the cannelure or make more cuts in the jacket to weaken it. one expedient way to do it is to use a small lathe. This enhances fragementation especially for the m4. for the other calibers you can make a cannelure or else just score the bullet right above the neck of the cartrige. that way you dont have to remove the bullet from its case , just put the whole thing on a lathe and scratch a groove above the cartrige lip. I think this will increase the lethality of other rifles, especially the p90 and mp7 bullets which some critics say are underpowered.

NOTE: this might be a violation of the hague convention

vmaldia, Oct 07 2006

military rifle bullet wound patterns http://matrix.dumps...un/basics/pmrb.html
[vmaldia, Oct 13 2006]

Dum-dum http://en.wikipedia.org/wiki/Dum-dum
This article shows that modifying bullets in the manner described has been widely researched and done with many different iterations. Specifically, the modification [vmaldia] mentions in the last paragraph is the one done by "poorly informed soldiers of many nations". This is widely known to exist, and thus [marked-for-deletion]. [bungston, Oct 13 2006]

my blog http://magos-biologis.blogspot.com/
[vmaldia, Dec 03 2009]


       you're a surgeon? drumming up business?
po, Oct 07 2006

       This idea seems carefully thought out and well explained. There's no rule that says HB ideas have to be frivolous and un-threatening. I'm not a gun fan, but I will bun this rather scary thing because of the good exposition and the nod to the Hague Convention.
pertinax, Oct 09 2006

       If, by //violation of the hague convention// you are referring to the "Declaration on the Use of Bullets Which Expand or Flatten Easily in the Human Body" adopted at the First Hague Peace Conference (1899):   

       "The Contracting Parties agree to abstain from the use of bullets which expand or flatten easily in the human body, such as bullets with a hard envelope which does not entirely cover the core, or is pierced with incisions."   

       i.e., it isn't the design, it's the effect. If you want a bullet that *looks* like it conforms to what people *think* the Hague Convention stipulated, then sure, fine. If you want a bullet that actually performs in such a way as to make your target go dead, this has been studied & tested to a fare-thee-well with hunting bullets. And by the way, a fragmenting hunting bullet is generally considered a very poor design, as the diverging fragments expend energy over a dispersed area of the target's body. Maximum kill performance has been found to be associated with having only one single wound channel. (Buckshot being less lethal than a slug, for example, and birdshot even less lethal than that.) However, to make sure that the total energy of the round is expended within the body, the wound channel is enlarged by expanding - "mushrooming" - the bullet.
lurch, Oct 09 2006

       in general for hunting larger game, fragmenting bullets are LESS desirable but we're talking of the special case of the 5.56 ammo on humans here. animals are build differently from humans and yes its theoretically possible to design bullets that are more lethal in large animals compared to humans and vice versa.   

       look at the link i posted to see some pictures (drawings actually) of rifle wounds. you'll see that the 5.56 is different from most fragmenting rounds. a fragmenting pistol bullet like a glaser fragments early with little penetration while a 5.56 penetrates to around 15cm before it yaws and breaks up. with a human hopefully that 15-25cm deep big bullet cavity will intersect a vital organ while with a glaser or with birdshot, the biggest diameter wound cavity is much shallower and its possible that deep vital organs wont be hit.
vmaldia, Oct 13 2006

       well, the difference between my idea and the dum dum bullets is that i'm making a groove around the middle of the bullet, not filing off the tip or cutting notches in the tip like the traditional dum dum. and i dont want expansion only, i want fragmentation
vmaldia, Oct 14 2006

       I'm just copying this old entry into my blog (see the link)
vmaldia, Dec 03 2009

       Well, thanks for the churn; I didn't get to bone it first time around.
AbsintheWithoutLeave, Dec 03 2009


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle