Shooting extremities
Originally posted by The_Fur
...those damn Americans don't run so fast with a couple 5.45mm rounds in their legs 
AKMSU: "The cure for the 'Running Dogs of Capitalism'"
Originally posted by BrownCow
Just out of curiousity, in the long run is the inf team planning on doing anything so people can't "shoot your feet to death"?
There is no feet. The player/bot target model is composed of two cylinders each with a vertical axis on top of one another. The upper one is the more-vulnerable Head and the larger lower one is the Body. At some stage in the future, the prone model will change to consist of the same two cylinders oriented with their central axis parallel to the ground. That is all, there is no feet, there is no legs, there is no chest, thorax, buttocks, groin, arms or hands: there is only the Body cylinder model. Its a characteristic of the design decisions made by the INF team and is a reasonable decision (IMHO) based on performance considerations for the range of machines that will be running INF. As time goes by and more detailed models are possible, both with future engines and CPU/video card speed improvements, then I'm sure the INF team will make changes to their model to make use of these improvements.
Thirty years ago showing the actual damage caused in combat by bullets and shell fragments would have been considered obscene. As a result, so many war movies depict quick, sanitised deaths of the characters for this reason, as well as being unable to simulate it even if they had wanted to. The advent of cheap computer graphics and improved special effects, as well as changing attitudes to viewing 'gore' has meant that you are starting to see more accurate depictions of damage to the human body in movies for entertainment. Consider
Saving Private Ryan which attempts to show the brutal nature of an assault in its first thirty minutes. Real battles are injuries are messy and brutal and not anything you're likely to see an Arnold Schwartznegger movie.
So let's look at what happens if you get shot in the arm or leg.
If you are shot in the arm/leg, then you might be lucky and still able to fight on after more than one 'flesh' wound. You might also be unlucky and have a bullet hit the bone in your upper arm and almost take it off when the bullet disintegrates, your humerus disintegrate under the impact, your nerves, tendons, veins, arteries, muscle and skin are ripped off the back of the arm by bullet or bone fragments and you are left with an arm hanging by the remaining skin and muscle. Strictly speaking you aren't dead, but you will almost certainly be out of the fight from shock or pain.
http://www.palestinercs.org/bullet_injury_types_&_care.htm
Destabilization causes retardation- the5.45mm bullet of AK 47, the latest and the most effective rifle what is particular about this bullet is the air filled space in its nose. On hitting the target, the heavy –lead atimony core is pushed forwards; the bullet becomes very instable and starts rotating inside the wound track. In a thigh hit this causes a maximum cavitation close to the femur, the main nerves and vessels. Similar to it, is 5.56-m bullet of M16 rifle.
Fragmentation causes retardation- hitting bone, most bullets become deformed or broken into fragments, finding the main cavitation on the outlet side of the fracture. Also, bone fragments are accelerated into the tissue as secondary projectiles, adding to the cavitation. Energy shock waves may also travel the bone, into structure close to the bone, and remote organs may be damaged.
How do the tissues tolerate cavitation?
Every tissue has its particular features that also affect the wound track:
Skin is elastic and absorbs the cavitation well. It’s stretched and returns to normal without much necrosis.
The subcutaneous fatty tissue is elastic and has poor blood supply cavitation causes extensive necrosis due to small vessel destruction.
Muscle tissue is ever less elastic and will not absorb the cavitation, muscle cells are directly crushed by the pressure wave.
Also minor vessels are torn causing secondary hypoxia and muscle cell death.
Bone is not elastic at all “except children”. Compound fractures are common even if the projectile does not hit the bone directly. And the energy wave may travel along the bone and cause extensive necrosis in the muscle bellies and compartments close to the bone.
So it all sounds pretty serious if you are unlucky to be hit in the bone in the arm or leg. How often are you likely to be injured in the arm or leg in a battle? Doing some research on the Internet yields the following information.
http://www.bosnet.org/archive/bosnet.w3archive/9502/msg00183.html. Note the quoted 'normal' percentage of wounded with injuries to extremities. Note that some of these would have multiple injuries to extremities and body/head.
Injuries to extremities, which has averaged 60-70% in contemporary conflicts amounts to 73% in Sarajevo.
http://salata.mef.hr/CMJ/3802/3802-8.htm contains statistics on the injured treated in a Croatian hospital 1991-1995. Note that these statistics on injuries to extremities are almost certainly biased since many victims of fatal trunk, neck and head injuries would not make it to the hospital to be included as part of these statistics.
The prevalence of the war wounds of the extremities have been reported to range between 71-73%. We encountered 88.3% of such wounds, with the domination of injuries caused by the explosive devices. There was about 61.1% of the wounds of the lower extremities, and 27.2% of the upper extremities. The wounds were mostly complex with the associated injuries of bones, joints, tendons, blood vessel and nerves, and in 73.4% of the cases they were classified as type III injuries(Adequate soft-tissue coverage of a fractured bone despite extensive soft-tissue laceration, or high-energy trauma irrespective of the size of the wound, or extensive soft tissue loss with periosteal stripping and bone exposure: usually associated with massive contamination, or open fracture associated with arterial injury requiring repair.)
Trauma in the Afghan guerrilla war: effects of lack of access to care.
...
The
ratio of critical-area wounds (trunk, head and neck)/extremity wounds was low (0.07) compared with most other wars (about 0.50), indicating that the most seriously injured patients died before treatment was obtained.
Of course you could be lucky: (Note that the AKMSU and AK47 terminal ballistics are different.)
http://rkba.org/research/suter/trask.rebuttal
AK47 wounds more closely approximate handgun injuries with non-expanding bullets.
...
Reports from Vietnam confirmed the often minimal wounds caused by AK-47 bullets: "Uncomplicated perforating soft-tissue wounds were the most common bullet wounds of the extremities; They showed small entry and exit wounds and a clean soft tissue track with little or no devitalization of tissue. They usually healed if left alone."
So, the bottom line seems to be that about 50% of wounded people are wounded in the arms or legs, but that these are much more survivable than wounds to the body or head if immediate medical aid is not available. This figure of 50% may be of use to the INF team in designing future versions.
Bill Lee
PS: Largest arteries: Aorta, then Pulmonary, although the liver, spleen and skin are reservoirs for about 20% of our body's blood. The femoral artery carries 300-900ml of blood per minute (
http://www.ecr.org/T/ECR97/sciprg/abs/9700314o.htm). As you can imagine, you could lose a lot of blood from a damaged femoral artery very quickly.
