Bullet energy transfer

[fullautovalmet76]

Yeah, just as I expected.  That link is from 1998.   

LOL!

At least they did us the service of dating their work.

Tyler,
Modern Calculus is over 300 years old. Do you think it's automatically invalidated because of its age?

[Tyler Durden]

You have to read and understand that this quoted section below is from that link date 1998:

There have been many police officers here in the United States who've been shot with medium-high energy Magnum handgun bullets (as well as shotgun slugs) while wearing soft body armor. Soft body armor is constructed of several layers of fabric. When a projectile impacts soft armor, its energy is transmitted directly through the flexible fabric to the officer's body. There's not one documented incident in which an officer was knocked unconscious or physically incapacitated or in any way rendered unable to perform willful activity after his soft armor stopped such a projectile. These officers absorbed nearly 100 percent kinetic energy transfer, yet none were incapacitated by the blunt trauma "shock" of projectile impact or temporary displacement of underlying soft tissues.

2010 minus 1998 = 12 years

Like I said there have been a lot of officer involved shootings since 1998, probably enough to rule out the "none" part or the "There's not one documented incident...." part of the quoted section above.

Just because something might have happened prior to 1998 and was not documented, it doesn't mean that it did NOT happen.

The internet in 1998 was still kinda in its infancy. 

For example, if I am reading this chart correctly:

http://finance.yahoo.com/echarts?s=GOOG#chart1:symbol=goog;range=my;indicator=volume;charttype=line;crosshair=on;ohlcvalues=0;logscale=on;source=undefined

Google didn't have its initial public offering (IPO) until 2004.


I do remember my roommate in the 94, 95 or 96 timeframe had his nose completely buried in AOL chatrooms with a dial up connection.  I doubt that many police departments in that same time frame were real quick to broadcast on the internet that their Officer Joe Sixpack got shot with a .38 Special, but was still able to return fire and apprehend the suspect.

Said another way...departments might have been hesitant to broadcast to the rest of the world that either their training sucked or that their TTP's sucked as well.

[fullautovalmet76]

You have to read and understand that this quoted section below is from that link date 1998:

2010 minus 1998 = 12 years

Like I said there have been a lot of officer involved shootings since 1998, probably enough to rule out the "none" part or the "There's not one documented incident...." part of the quoted section above.

Just because something might have happened prior to 1998 and was not documented, it doesn't mean that it did NOT happen.

The internet in 1998 was still kinda in its infancy. 

For example, if I am reading this chart correctly:

http://finance.yahoo.com/echarts?s=GOOG#chart1:symbol=goog;range=my;indicator=volume;charttype=line;crosshair=on;ohlcvalues=0;logscale=on;source=undefined

Google didn't have its initial public offering (IPO) until 2004.


I do remember my roommate in the 94, 95 or 96 timeframe had his nose completely buried in AOL chatrooms with a dial up connection.  I doubt that many police departments in that same time frame were real quick to broadcast on the internet that their Officer Joe Sixpack got shot with a .38 Special, but was still able to return fire and apprehend the suspect.

Said another way...departments might have been hesitant to broadcast to the rest of the world that either their training sucked or that their TTP's sucked as well.

I had to re-read your post several times before I got it, I think. So bear with me. 

I understood the original article is from a web site that draws heavily from the research of Dr. Martin Fackler, a surgeon who served in Vietnam (sewed up a bunch of kids over there...). And one of Fackler's pet peeve's was the research (he would say supposed research) from Sanow (can't remember the other guy) about one-shot stops. In short, he thought their research was absolute rubbish. Fackler wrote several articles describing how wound ballistics work. He found that heavier, slower handgun bullets penetrated deeper and caused the most internal damage versus faster, lighter bullets of the same caliber. He also said that unless one got a shot on the central nervous system it would be very unlikely to stop someone with one shot.

I believe the article is furthering Fackler's arguments. The article references several concepts from the field of physics with the message that the energy transfer notion is not valid. When you pointed out the article was from 1998, I thought I would have some fun with you; I'm sorry if you took it personally.

So the larger point of the article is not what you really think its about. You need go read other articles on the site and you will understand what I'm writing about. Here's a link to get you started: http://www.firearmstactical.com/wound.htm

-FA

[Tyler Durden]

Oh, NOES!  I didn't take it personally.  This is the internet and you're some anonymous person.  I try NOT to let anonymous people rent space in my head (hey, there is only so much room....  ).

Heck, the people that I know and see on a daily basis...well...I try NOT to let them rent space in my head either.   

[m25operator]

I'm normally the 1st guy to call BS on such info, with soft body armor you would think, that being hit by a 1 oz slug would be the equivalent of being hit by George Forman, Muhammed Ali in the chest, no penetration but a lot of energy transfer.

Watching Richard Davis ( 2nd chance body armor ) on video that is absurd, I saw the 1st version where he shot himself in the chest 3 times with a .357 mag, and then shot 3 bowling pins to demonstrate his vest was able not just to protect, but allow return fire. As crazy as I have been in my life, I'm not going to test a vest on myself, no matter how much I believe in it.

But here is Richard from 1986 proving his product. Quality is low, effect is high.


http://www.youtube.com/watch?v=aaS_2l8nGdg

[Sponsor]

[Tyler Durden]

^^^ at the 4:58 mark, why does he hold the revolver at such a wierd angle?

Is he "gaming" the demo by receiving a glancing blow?

[m25operator]

Tyler I think it had more to with shooting a full house .44 mag, and how he had to hold it to shoot at himself and still control it. I have never tried it ( shooting with that type of grip ) and don't plan to any time soon.

[sledgemeister]

An interesting thread in light of a recent story in the news atm.

http://www.news.com.au/world/falling-bullet-kills-four-year-old-boy/story-e6frfkz0-1225815908833

A FALLING bullet shot during New Year's Eve celebrations has tragically killed a four-year-old boy.

The boy, Marquel Peters, was inside a church in Decatur, Georgia, playing a video game when he suddenly collapsed at his parents feet, WSTV reports.

A police spokesman Jason Gagnon said it appears the bullet came through the church’s roof and struck Marquel in the head.

Marquel's parents were initially unaware of his injuries until blood started gushing from his head.

"I saw his Nintendo game fall on the floor, and I heard a sound and I heard him scream a little bit and I looked around and all I saw was blood coming from his head," Marquel's mother, Nathalee Peters,  told Channel 2 Action News.
Attempts to keep Marquel alive at the church and later at a nearby hospital were unsuccessful.
"No one knew what it was," Marquel's uncle Garry Peters told WSTV.
"It was just crazy."

Ballistics expert  Kelly Fite told the Atlanta Journal-Constitution newspaper that the bullet had most likely been fired from an AK-47 assault rifle and could have been fired as far as  three to five kilometres away.
The church's pastor, Lloyd Phipps, told The Atlanta Journal-Constitution  that the youngster's death made no sense.
"It's one of those things that you just cannot make any sense out of," Mr Phipps said.
"This lady took her kid to church, which is the right thing to do. And her son got killed because of someone’s irresponsible behaviour."
Police are yet to make any arrests but are 'actively pursuing leads'.

Forget the emotive stuff for a moment and think about the physics of such a feat.
1) an ak round going that far (if of course it was fired by an ak - but I guess that sounds more scary than a cz B/A chambered in 7.62x39)
2) what momentum would it have left at that sort of distance, if of course its possible to even go that far. Also consider it had to go thorugh a roof, presumably not made of tissue paper.

[tombogan03884]

 If the bullet had been fired straight up it would have had to come to a complete halt before it began falling, and while it might have messed him up it would not have killed him since the terminal velocity is determined by the weight of the falling object and at 125 Gr. would not have been that great.
Being shoot at an upward angle however the bullet may start dropping due to loss of velocity but it is still traveling under propulsion rather than simply gravity and it's speed can be greater causing serious injury.
That being said to retain that much energy after coming through a roof, doesn't sound right.

[Timothy]

Terminal Velocity

125 Gr bullet, .30 dia with a cross section of .0707 sq in at medium density air is traveling about 282 ft/second based on this calculation using a 0.30 drag coefficient. And this is assuming the bullet is falling straight down pointy end first....

http://www.calctool.org/CALC/eng/aerospace/terminal

Might get through the roof, kill someone?  Doubt it!