View Full Version : Does it really matter?
I have seen--and debated/considered/thought about/asked about--a lot of questions regarding minuscule differences in ammunition performance.
We can reasonably state that TapT2 is going to do more total damage than M193.
We know that LE223T3 is going to go through car windshields much better than TapT2.
However, if you are NOT ENGAGING a target behind a barrier, is there any point sweating it? Have you people who go to exotic places to stop bad people seen these people take multiple hits to the thoracic cavity and keep coming?
Is M193 or M855 not stopping these people (of any other people, Americans, whatever, when used by LE, don't want to discriminate...) when the vital organs of the thoracic cavity are encountered?
That being said, I just bought 250 rounds of the 50gr TSX 5.56 and a 500 round case of MK318, so yes, I believe that better...is better, and the barrier-blind stuff is more versatile, I just want to know if M855/M193 is truly failing to do the job when people put it in the right place.
Great thread! Looking forward to hearing some response.
Pretty much any projectile, even a .22LR will generally cause incapacitation when unobstructed shots are precisely placed into the cranial vault, upper spinal column, or heart/great vessels. The problems occur when shots are a little bit off in placement, when the opponent is not standing still in frontal anatomic position, when the opponents anatomy diverges from ideal, when intermediate obstacles intervene; then projectiles with adequate penetration, good intermediate barrier capability, early upset, and all the other factors inherent in improved terminal performance can make a decisive difference in the outcome of a lethal force encounter.
Pretty much any projectile, even a .22LR will generally cause incapacitation when unobstructed shots are precisely placed into the cranial vault, upper spinal column, or heart/great vessels. The problems occur when shots are a little bit off in placement, when the opponent is not standing still in frontal anatomic position, when the opponents anatomy diverges from ideal, when intermediate obstacles intervene; then projectiles with adequate penetration, good intermediate barrier capability, early upset, and all the other factors inherent in improved terminal performance can make a decisive difference in the outcome of a lethal force encounter.
I understand, but M193 penetrates a minimum of 12-14" unless a windshield, etc. comes first.
I cannot see where .40" vs. .224" is going to be a deal-breaker (TSX vs. M193) if one of these structures is hit. If it is missed, well, a miss is a miss and a dedicated individual or one on drugs won't notice .40" holes through their limbs as any more painful than .224" holes, I would imagine.
There is DEFINITELY a need and desire to use barrier blind ammunition for some people. However, for an AR-15 that will rest beside one's bed and be grabbed if the window is jimmied, is there any advantage to running Tap T2 over M193 aside from the academic?
I suppose you can argue (and rightly so) that 3 seconds less on the feet is a lot less lethal than 3 seconds more on the feet, and I agree.
My main point is made in reference to people who are selling all their M855/M193 to buy 20% as much T2 or SOST, etc.
I understand, but M193 penetrates a minimum of 12-14" unless a windshield, etc. comes first.
I cannot see where .40" vs. .224" is going to be a deal-breaker (TSX vs. M193) if one of these structures is hit. If it is missed, well, a miss is a miss and a dedicated individual or one on drugs won't notice .40" holes through their limbs as any more painful than .224" holes, I would imagine.
There is DEFINITELY a need and desire to use barrier blind ammunition for some people. However, for an AR-15 that will rest beside one's bed and be grabbed if the window is jimmied, is there any advantage to running Tap T2 over M193 aside from the academic?
I suppose you can argue (and rightly so) that 3 seconds less on the feet is a lot less lethal than 3 seconds more on the feet, and I agree.
My main point is made in reference to people who are selling all their M855/M193 to buy 20% as much T2 or SOST, etc.
The problem is that fragmentation out of the 5.56, particularly with FMJ is an unreliable wounding mechanism. The bullet has to destabilize, yaw, and then fragment. This does not always happen even under the best conditions. Also, if the angle of attack isn't ideal, the necessary 4" of flesh penetration to cause destabilizing isn't there, or the bullet wasn't manufactured well enough for good breakup you will have additional unreliability. The body will always have around 65% water in it, and expansion rounds will often reach maximum bullet diameter in only 2" of penetration and retain high momentum to break through bone and cause deep penetration. There is a reason why most hunters stick with expansion loads on medium to large game.
More wounding is always better. More reliable wounding is better still. Precision shooting is not always possible, then you must often rely on the trauma of your projectile. Handgun Wounding Factors and Effectiveness applies to rifles/shotguns in concept as well. More tissue damage is the key when precision is not easy. Here's an old article by Dr. Fackler on the Stockton, CA shooting:
http://www.uthr.org/SpecialReports/Martin%20Fackler,%20Stockton%20case.txt
Notice how many people recover from 7.62x39 torso hits, along with other rifle projectiles. Obviously it is important to use reliable expansion/fragmentation bullets particularly in 5.56. Fackler has also seen quite a few M193 hits out of a M16 20" 1:12 twist in which the bullet did not fragment. Very few recover from 12 gauge buckshot torso hits due to the increase level of wound trauma.
Here's the order of terminal effects importance. #1 must be fufilled before you can move on to #2, then #3.
1) Deep penetration to reach the large blood bearing organs of the body, and defeat common external and internal barriers.
2) A reliable, and viable wounding mechanism through projectile/projectiles shape. Rounding or pointed projectiles often squeeze through tissue with minimal damage and temporary cavity stretch. The projectile needs to deform into a flat frontal area such as an expanded JHP to cause adequate crushing/tearing of tissue. A yawing/tumbling projectile makes a little more trauma than a FMJ projectile that does not yaw/frag, but its wound volume is still fairly minimal. A fragmenting projectile also meets this requirement, but it often isn't as reliable a mechanism and often fails to meet #1.
3) Lastly, the size of the wound comes into play. A deep penetrating, reliably expanding 9mm JHP is superior to a .45acp FMJ. #1 and #2 come before caliber selection(#3).
Is using M193/M855 a sound decision? If you have limited financial resources, sure. Are there better choices that "could" determine the outcome of your deadly force encounter, sure. I'm guess that MK318 will be down to around $.50 a shot in the near future, so if you are on a budget that might be the best option.
I have been hearing a lot about this mk318 price drop latley. I thought it would just go up from here. Can someone explain why is would become less expensive? When do you expect this to happen?
I have been hearing a lot about this mk318 price drop latley. I thought it would just go up from here. Can someone explain why is would become less expensive? When do you expect this to happen?
Supply and demand. I'm not sure on the cost of manufacturing MK318, but it should not be significantly more than M855....if not similar in manufacturing cost. So, once the supply gets closer to M855 levels, then you will see the price difference become less and less.
I have seen--and debated/considered/thought about/asked about--a lot of questions regarding minuscule differences in ammunition performance.
We can reasonably state that TapT2 is going to do more total damage than M193.
We know that LE223T3 is going to go through car windshields much better than TapT2.
However, if you are NOT ENGAGING a target behind a barrier, is there any point sweating it? Have you people who go to exotic places to stop bad people seen these people take multiple hits to the thoracic cavity and keep coming?
Is M193 or M855 not stopping these people (of any other people, Americans, whatever, when used by LE, don't want to discriminate...) when the vital organs of the thoracic cavity are encountered?
That being said, I just bought 250 rounds of the 50gr TSX 5.56 and a 500 round case of MK318, so yes, I believe that better...is better, and the barrier-blind stuff is more versatile, I just want to know if M855/M193 is truly failing to do the job when people put it in the right place.
The way I see it is, be prepared for the worst possible case. There is no 100% guarantee that you will not engage someone that will take cover.
Bullets (like M855 and M193) that have substantial AOA and fleet yaw issues, along with other variances leading to inconsistent terminal performance are not optimal choices, as Dr. Fackler noted here: https://www.m4carbine.net/showthread.php?t=26905.
Using equivalent machinery, Mk318 is actually easier and cheaper to manufacture than M855.
The way I see it is, be prepared for the worst possible case. There is no 100% guarantee that you will not engage someone that will take cover.
Right. I always like it when people tell me that they will NEVER have to shoot at someone through a barricade. Really? How do you know that???
C4
Right. I always like it when people tell me that they will NEVER have to shoot at someone through a barricade. Really? How do you know that???
C4
While I plan on stockpiling M193/M855, I did order a few hundred bucks worth of barrier blind ammo from you, which arrived promptly and in great shape. :cool:
I'm also tempted to just stockpile a few thousand rounds of SOST ammo.
Right. I always like it when people tell me that they will NEVER have to shoot at someone through a barricade. Really? How do you know that???
C4
I live and work in a barricaded world; car doors, windshields, airplane fuselages, doors, walls, fences, etc. For me, post barrier performance is crucial. It is why I carry a .40S&W primary and a .357Magnum BUG. I understand that our 64gr Speer rifle ammo has excellent post barrier performance although I have yet to but it to test. In some infomal testing we conducted on our typical barriers described above (we shot up a car) the Speer performed very well.
In the end an individual makes the choice of what is enough and does it matter.
As a civilian all you likely need is to point a gun/any gun, from there if that fails then shoot and don't even need to hit anything in particular, if that fails you get down to needing performance. If you want to be best prepared then you go maximize the effectiveness and versatility of the rounds as much as possible.
So what point is good enough.
Bullets (like M855 and M193) that have substantial AOA and fleet yaw issues, along with other variances leading to inconsistent terminal performance are not optimal choices, as Dr. Fackler noted here: https://www.m4carbine.net/showthread.php?t=26905.
Using equivalent machinery, Mk318 is actually easier and cheaper to manufacture than M855.
Doc, may I ask what "AOA" and "fleet yaw" issues are?
Thanks.
Angle-of-Attack (AOA) variations between different projectiles, even within the same lot of ammo, as well as Fleet Yaw variations between different rifles, were elucidated by the JSWB-IPT (Joint Service Wound Ballistic Integrated Product Team). These yaw issues were most noticeable at close ranges (usually under 25 m) and were more prevalent with certain calibers and bullet styles.
Projectile impact angle-of-Attack (AOA) variability is caused by bullet to bullet variations at impact and can substantially alter wound severity; this factor is more prevalent with certain calibers and projectile types. Testing demonstrated that 5.56 mm is highly susceptible to AOA variations, particularly when using military style FMJ projectiles such as M193 & M855. For example, with 5.56 mm FMJ's striking at higher AOA’s, for example 2-3 degrees, bullets demonstrated a shorter neck length (NL) and upset rapidly, thus providing adequate terminal effects; when impacting the target at a low AOA such as 0-1 degree, the projectiles penetrated deeper than ideal prior to initial upset (ie. long NL) with significantly reduced terminal effects. AOA follows a sine wave style pattern--for example offering a 0.5 degree AOA at 3 m, widening to a 3.5 degree AOA at 4m and back to 1 degree at 5m. Note that other calibers were less susceptible to AOA variations than 5.56 mm, OTM’s tend to have less AOA issues than FMJ, while PT and JSP’s tend to not have major AOA induced terminal performance changes.
Fleet Yaw is the terminal performance AOA variation caused by inherent variability in each rifle; Fleet Yaw is caused by weapon to weapon variations separate from projectile induced AOA issues.
The effects of AOA and Fleet Yaw can result in two shooters firing the same lot of M855 from their M4’s with identical shot placement, yet they observe dramatically different terminal performance results: one shooter states that his M855 is working great and is effective at dropping bad guys, while the other complains his opponents are not being incapacitated because M855 is zipping right through the targets without upsetting. Both shooters are telling the truth… Restricting M855 for what is was designed for--use in the SAW and simply adopting new 5.56 mm barrier blind combat loads that are optimized for carbines with shorter barrels, offer consistent early upset, along with adequate penetration, and minimal AOA/Fleet yaw issues may be the critical answer to many deficiencies noted with currently issued U.S. military 5.56 mm ammunition.
I...
I cannot see where .40" vs. .224" is going to be a deal-breaker (TSX vs. M193) if one of these structures is hit. If it is missed, well, a miss is a miss and a dedicated individual or one on drugs won't notice .40" holes through their limbs as any more painful than .224" holes, I would imagine.
...
Its not .4 vs .224" Take into account the hydrostatic shock which, as I understand IS a viable wounding mechanism for rifle rounds (but not pistols). A .223 that does not tumble will make a very small wound channel. A .223 that expands to .4" traveling at a high velocity will cause a large amount of tissue damage surrounding the bullet path.
This will give a little room for error, but the main thing is that the larger damaged area will lead to much quicker end to the fight.
defense isnt about killing your adversary, its making him stop before he kills you.
Which runs farther, a deer shot with a field tip or a broadhead? Its only a .7" diameter difference.
193 and 855 cannot be relied upon to tumble and frag when and where you need it to.
Doc,
I take it that most barrier blind expansion bullet designs greatly reduce the problems of AOA and fleet yaw in the 5.56?
Its not .4 vs .224" Take into account the hydrostatic shock which, as I understand IS a viable wounding mechanism for rifle rounds (but not pistols). A .223 that does not tumble will make a very small wound channel. A .223 that expands to .4" traveling at a high velocity will cause a large amount of tissue damage surrounding the bullet path.
This will give a little room for error, but the main thing is that the larger damaged area will lead to much quicker end to the fight.
defense isnt about killing your adversary, its making him stop before he kills you.
Which runs farther, a deer shot with a field tip or a broadhead? Its only a .7" diameter difference.
193 and 855 cannot be relied upon to tumble and frag when and where you need it to.
The one that gets shot in the "WRONG" place. Don't forget that shot placement is first and foremost!
KhanRad--Correct. That is why the newest generation of military 5.56mm projectiles (SOST, A1, Opitmal) have all been designed to have less AOA issues...
FWIW, this is also one of the reasons that 6.8mm so dominated the JSWB-IPT testing, as it exhibited virtually no AOA or Fleet Yaw issues and performed very consistently at ranges under 300 yds.
Doc, have you done any tests with thin jacket FMJ 7.62 NATO ammo?
This paper mentions that at the old danish load still fragmented reliably at 2345 fps, that's about 150+ m if your muzzle velocity is about 2680 fps, normal for a 45 cm/ 17.7" barrel like a G3 or FAL para:
http://www.springerlink.com/content/q07948p717287257/fulltext.pdf
Do the thin jacket 7.62 N loads also suffer from AOA issues? What is the common neck lenght range for these loads?
Besides AOA issues, is there any downside to these loads?
Do they penetrate common intermediate barriers just as well (or bad) as normal, non fragmenting FMJ bullets of the same caliber?
Is there any maker that still makes thin jacketed FMJ 7.62 NATO rounds that behaves like this?
KhanRad--Correct. That is why the newest generation of military 5.56mm projectiles (SOST, A1, Opitmal) have all been designed to have less AOA issues...
FWIW, this is also one of the reasons that 6.8mm so dominated the JSWB-IPT testing, as it exhibited virtually no AOA or Fleet Yaw issues and performed very consistently at ranges under 300 yds.
Time to get a 6.8mm upper just in case...:laugh:
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