AR15.Com Archives
 5.56 & Stopping Power
creedekid  [Member]
3/22/2009 8:54:58 PM
I came across this on the S&W forum and thought it was interesting.

____________________________________________________________________________________

Below is an interesting post from the Insights Training Center email
list regarding the perennial 5.56 vs .308 debate.
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Refs:
http://www.thegunzone.com/
http://www.strategypage.com/mi...ryforums/1-3983.aspx
http://www.thehighroad.org/showthread.php?t=229005
http://www.abovetopsecret.com/forum/thread142560/pg1
http://www.insightstraining.com/

====================================================
xxxxx posted (<03/08/2009)

I was reading an article written by Paul Howe (can't find the article now, though)
where he said that the 5.56 round does not have the necessary stopping power,
and cited real-world experiences where the BG's did not stop fighting fast enough
after being shot with a 5.56 round(s). He felt that the 7.62 round was superior,
and therefore recommended the FAL as a general-purpose fighting/defensive rifle.

Which leads to my questions:
Is this view common amongst his peer group?
Why does Insights prefer the AR-15/M-4 over the FAL?

I haven't discussed this with Paul in depth but will next time I talk with him. I'll let
you know his response.

I did attend Paul's" High Risk Operator Instructor Course" a couple of months ago
(the shooting was about 80% rifle.) Paul shot his own AR (5.56) during the class.
In our equipment discussions during the course he did not have anything negative
to say about either the 5.56 cartridge or the AR platform.

I have also heard Paul give his talk on the "Black Hawk Down" mission in Mogadishu.
He did mention dissatisfaction with a situation(s?) where he shot someone and they
ran away (or had to be shot again). IIRC he was shooting M855, out of a short barrel-
ed rifle at targets a couple of blocks away and they didn't appear to react.

This doesn't surprise me because M855 out of a 14.5" barrel only has enough velocity
to reliably fragment out to about 100yds. Once the bullet is moving slow enough that
it doesn't fragment, it tends to simply drill a 5.56mm (0.4688"or 15/32") hole through
the tissue. If that hole isn't in brain, spine or significant bone there is no reason the
man will have to react immediately to being shot.

Which brings us to the time element of the equation. How quickly can we expect
a bullet to terminate hostile activity; 1-3 seconds, 3-5 seconds, 5-10 seconds?
How fast is fast enough?

If the BG continues his violent assault for 5-10 seconds after being shot by his intend-
ed victim I expect the defensive shooter will quite likely feel his shot was "ineffective."
Even a period of only 3-5 seconds can seem to be an eternity in a fight, and of course
the BG can do a lot of damage (or run out of sight) in that time. The fact is however
that no matter how much tissue damage is done to the heart, lungs, or most other
bodily structures; wounds to those structures will not reliably shut a person down in
less than 3-5 seconds (and often much longer.) This is regardless of the caliber of
the projectile causing the wounds. Hits to the brain or spinal cord are the exception
and often, but not always, produce more immediate results.

A couple of years ago I reviewed an LE shooting where a BG was hit 12 times with
an AR at a range of 9-12 yds. 10 rounds struck his torso producing fatal damage to
his liver, spleen, heart and both lungs.1 round struck his right femur fracturing same
(and starting his fall toward the ground.) 1 round entered through his left eye and
destroyed a significant portion of his brain (this was the last shot according to
forensics but they noted the BG was already falling at the time this round hit him.)

The shooting was captured on both video and (separate) audio recordings. The
elapsed time from the LEO's first shot to his 15th shot (total rounds fired) was just
under 5 seconds. During those 5 seconds the BG continued to fight, firing 6 rounds
from a .357 revolver. Having viewed the autopsy photos of the BG's heart, lungs,
liver and spleen I can tell you that the contents of his torso were pretty much trashed.
I just don't' believe that some other caliber would have made a significant difference
in the amount of damage. Trashed is trashed.

Was this a failure to stop? I spoke with the LEO shooter a couple of days after the
incident and that was certainly his perception. He commented that he got really
tired of seeing the big muzzle flash come out of the BG's gun and just wanted it to
stop. (The shooting took place at night in low light conditions.) Early in our conver-
sation he asked me what round they could use which would incapacitate a BG
quicker. My answer was that I didn't know of any weapon/caliber, that he could
physically carry, which I would expect to do any better.

My point here is that I believe many of the "failure to stop" incidents are based on
unrealistic expectations of what a bullet (any bullet) can do. Somehow we don't
find it surprising when a deer is shot in the heart/lungs with a .308 or 30-06 rifle
and runs 25 yds or more (sometimes much more) before dying, but if a human
doesn't immediately expire in-place when shot we think we need a different
weapon/caliber.

I don't spend much time at all worrying about which caliber or particular load to
use in my defensive weapons. I want to spend the minimum time necessary to
select the cartridge I will use, because I know that developing the skill to deliver
them is a time consuming process. (Time, in life seems to be a zero-sum equation.)

My approach is to do enough research to insure that I have a round which seems
to go deep enough to get to the "good stuff" and expands/fragments reliably. In
most calibers there are numerous loadings which meet this requirement. I don't
really care which one of these I use.

Next I want to insure that particular cartridge is reliable in my gun.

After that it's all about developing the skills necessary to accurately deliver as
many of those rounds as possible in the shortest amount of time.

So what do I shoot in my AR? (14.5" barrel, 1:9 twist)

Mostly Federal 55 gr BTHP (why: because an LE agency I do training for paid me
partially in ammo and it meets the criteria.)

Or

M855 (cause a found a lot of it cheap a while back.)

IF I lived in an apartment or townhouse with neighbors only a few paper thin walls
away, I wouldn't feel too bad with the Black Hills 60gr VMAX. I know it doesn't pene-
trate "deep enough" in the tests but many things in life are a compromise and if
over penetration was a higher priority on my list of criteria..

wtturn  [Member]
3/22/2009 9:01:08 PM
I guess that's why I have an AR chambered in 6.8 instead.
GeorgiaBII  [Member]
3/22/2009 9:05:35 PM
People dislike holes in them. Shoot them and they will stop.

Posted Via AR15.Com Mobile
Slipey76  [Member]
3/22/2009 9:14:29 PM
Originally Posted By GeorgiaBII:
People dislike holes in them. Shoot them and they will stop.

Posted Via AR15.Com Mobile


QFT! Regardless if there is hardly any stopping power it is still going to hurt like a bitch. I do not care what caliber it is I do not want to be shot by any of them.
redleg71  [Team Member]
3/22/2009 9:24:00 PM
I'm very comfortable with 5.56 in large quantities. Though I have to admit, in a close quarter/home defense type situation; I'd much prefer 12 gauge with #1 buck.
DKing  [Team Member]
3/22/2009 9:38:23 PM
500S&W or go home
puppis  [Life Member]
3/22/2009 10:38:16 PM
Originally Posted By DKing:
500S&W 470 Nitro Express or go home


I fixed it for you.
LARRYG  [Team Member]
3/22/2009 11:02:37 PM
DKing  [Team Member]
3/22/2009 11:04:57 PM
you're a trekkie Larry?
TisforTennessee  [Team Member]
3/22/2009 11:21:57 PM
Trekkie Trekkie Trekkie
LARRYG  [Team Member]
3/23/2009 7:35:12 AM
Originally Posted By DKing:
you're a trekkie Larry?


No, I just like that clip to signify "not this shit again".
JT_26  [Team Member]
3/23/2009 8:33:05 AM
Once again we must realize that the movies are not real life. BG's don't just fall like dead weight after being shot like they do on tv.
LaRue556  [Member]
3/23/2009 8:38:34 AM
Originally Posted By GeorgiaBII:
People dislike holes in them. Shoot them and they will stop.

Posted Via AR15.Com Mobile


Yes.......I agree.

Caliber selection should be like ice cream. You choose your favorite flavor, and I'll choose mine.


BookHound  [Dealer]
3/23/2009 9:46:59 AM
Bad guys and zombies stop being a treat when they drop their gun and decide to play nice or they are incapacitated. The way to incapacitate a threat is either through blood loss or a hit to the CNS (Central Nervous System). This is why shot placement is often brought up as a more important factor than projectile size or type. If you could stick a high-velocity .22lr through someone’s spine and actually sever the cord, you might stop the threat faster than several much larger rounds through soft organs. The hits to the soft organs might even prove fatal but the threat may still be in the fight until the pump stops working.

There are now also projectiles, such as 75-grain TAP, that appear to be more destructive than other 5.56 projectiles such as the M855 ammo the military issues. Since we civilians don’t have to comply with the silly Hague Conventions (yeah, that’s a whole other thread we can debate), we can choose better projectiles for our personal protection needs. Would I rather shoot Mr. Zombie with a .50 BMG to the head instead of a couple 5.56 rounds to the stomach? SURE! But as much fun as it is to shoot LarryG’s ultra cool .50 BMG rifle it isn’t a practical house clearing weapon due to size, weight and ability for fast follow-up shots.

All these weapons have their place. In some situations I’d be grabbing the FAL and a few dozen magazines. In other situations you might find me behind the belt-fed in a sandbag bunker in the front yard sipping on a beer. And when the alarm goes off at night I’m grabbing my suppressed SBR loaded with 75-grain TAP and won’t feel under gunned in the least.

Debating calibers is a silly, futile exercise without considering various situations and the best solution(s) for that situation.

You guys all have a happy, blessed day and whatever you choose for self defense just remember to practice often and train hard.

Take care,

Mark
EOD  [Member]
3/23/2009 9:53:47 AM
Originally Posted By BookHound:
Bad guys and zombies stop being a treat when they drop their gun and decide to play nice or they are incapacitated. The way to incapacitate a threat is either through blood loss or a hit to the CNS (Central Nervous System). This is why shot placement is often brought up as a more important factor than projectile size or type. If you could stick a high-velocity .22lr through someone’s spine and actually sever the cord, you might stop the threat faster than several much larger rounds through soft organs. The hits to the soft organs might even prove fatal but the threat may still be in the fight until the pump stops working.

There are now also projectiles, such as 75-grain TAP, that appear to be more destructive than other 5.56 projectiles such as the M855 ammo the military issues. Since we civilians don’t have to comply with the silly Hague Conventions (yeah, that’s a whole other thread we can debate), we can choose better projectiles for our personal protection needs. Would I rather shoot Mr. Zombie with a .50 BMG to the head instead of a couple 5.56 rounds to the stomach? SURE! But as much fun as it is to shoot LarryG’s ultra cool .50 BMG rifle it isn’t a practical house clearing weapon due to size, weight and ability for fast follow-up shots.

All these weapons have their place. In some situations I’d be grabbing the FAL and a few dozen magazines. In other situations you might find me behind the belt-fed in a sandbag bunker in the front yard sipping on a beer. And when the alarm goes off at night I’m grabbing my suppressed SBR loaded with 75-grain TAP and won’t feel under gunned in the least.

Debating calibers is a silly, futile exercise without considering various situations and the best solution(s) for that situation.

You guys all have a happy, blessed day and whatever you choose for self defense just remember to practice often and train hard.

Take care,

Mark



Debating calibers is not futile. Ask the soldiers in the Phillipines. .38 would not stop the threat. .45LC would stop the threat. You can talk about shot placement all you want but there have been too many real life experiences where shooting paper does not equate to be shot at in real life with a BG coming at you.
BookHound  [Dealer]
3/23/2009 10:03:37 AM
Originally Posted By EOD:

Debating calibers is not futile. Ask the soldiers in the Phillipines. .38 would not stop the threat. .45LC would stop the threat. You can talk about shot placement all you want but there have been too many real life experiences where shooting paper does not equate to be shot at in real life with a BG coming at you.



But in some cases .38 does stop/has stopped the threat. That is my point.

The size of the projectile is only part of the equation.
saj195  [Member]
3/23/2009 10:11:08 AM
some projos do more damage than others.

i encourage everyone to study up on the mechanics of damage, making sure to understand the differences between lower velocity projos and high velocity projos.

re: the Hague Conventions
the beauty part is that US JAG determined that open tip match rifle bullets do not violate the Hague Conventions (no expanding hollow points by design, these match projos simply have open tip due to manufacture of the jacket being drawn from the rear toward the tip).
75gr & 77gr OTM FTW!
gajeep94yj  [Team Member]
3/23/2009 10:41:54 AM
Originally Posted By BookHound:
B Would I rather shoot Mr. Zombie with a .50 BMG to the head instead of a couple 5.56 rounds to the stomach? SURE! But as much fun as it is to shoot LarryG’s ultra cool .50 BMG rifle it isn’t a practical house clearing weapon due to size, weight and ability for fast follow-up shots.

Take care,

Mark


wuss!


GypsyDoc  [Member]
3/23/2009 2:01:32 PM
Here is a little info on the M855 from a ppt I have...

"M855 was designed over 20 years ago as machine gun ammunition to be fired fromM855 the M249 SAW at distances of several hundred yards, while engaging enemy troops wearing body armor during conventional infantry combat––it is adequate for this role.

Unfortunately, recent combat operations have again highlighted terminal performance deficiencies with M855 fired from the M4 carbine during CQB and unconventional warfare. These problems have primarily been manifested as inadequate incapacitation of enemy forces despite their being hit multiple times by M855 bullets.M855 bullets.

Current Threat Target: NOTE: Average threat anatomy since 11 September 2001.

Target Definition (Anthropometrical Dimensions)

Target is a Malnourished Southwest Asian or Middle Eastern male.

Definition of “malnourished" is a Body Mass Index (BMI) < 20.

Chakrabarty's "5th Percentile Indian Male" BMI = 17.8

Target “thickness” dimensions of the 5th percentile from Chakraborty are:
–Chest: 186 mm (7.32 inch).
–Waist: 191mm (7.52 inch).

In contrast, the average American soldier is 10 inches “thick”.

Some lots of M855 travel up to 7 inches before beginning to yaw and will have already exited the body before yaw or fragmentation occurs. So, with the current bad guy being between 7.32 in and 7.52 in thick, the round has already passed through before the real damage can be done.

Unfortunately, with decreased wounding effects, rapid incapacitation is unlikely and enemy soldiers may continue to pose a threat

Failure of M855 to yaw or fragment within tissue results in relatively insignificant wounds, similar to those produced by .22 long rifle bullets. This can be caused by:

Reduced impact velocities when the range increases or when fired from short barrel weapons.
When the bullet passes through only minimal tissue, such as a limb or the chest of a thin, malnourished individual.
Manufacturing variations in the composition, thickness, and relative weights of the jackets, penetrators, and cores, as well as the types and position of the cannelures."

That's the meat and potatoes of the M855. I hope this helps.



saj195  [Member]
3/23/2009 2:28:29 PM
yes, M855 is problematic for several reasons.
one of which is inconsistent manufacture due to its 3 part construction (lead, copper jacket, steel penetrator)

there are much better choices for 5.56mm use that are easily available.
ARH  [Member]
3/23/2009 2:34:29 PM
Better to hit with a BB than miss with a canon.

ARH

ugagrad06  [Team Member]
3/23/2009 3:29:52 PM
Originally Posted By BookHound:
Originally Posted By EOD:

Debating calibers is not futile. Ask the soldiers in the Phillipines. .38 would not stop the threat. .45LC would stop the threat. You can talk about shot placement all you want but there have been too many real life experiences where shooting paper does not equate to be shot at in real life with a BG coming at you.



But in some cases .38 does stop/has stopped the threat. That is my point.

The size of the projectile is only part of the equation.


that's what she said?
poison123  [Member]
3/23/2009 3:50:37 PM
Pfft. Hey if you can't do shot placement just shoot them alot. Someone joked with me that someone's ideal Home Defense weapon would be a Short Barreled PKM with AP ammo :)
Greenfeet  [Member]
3/23/2009 5:03:08 PM
There is always the physiological fact that he's not dead until his brain ceases to function, and if you don't shoot him in the brain, he's alive until the organs fail to deliver blood/ O2 to the brain.

So if you shoot him in the heart, it could take the rest of your life for him to die because his brain will keep functioning long enough for him to keep pulling the trigger. None of this "Dead before he hit the ground" stuff, regardless of caliber.