Does it really matter?

[WS6]

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.

[kenndapp]

Great thread! Looking forward to hearing some response.

[DocGKR]

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.

[WS6]

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.

[KhanRad]

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/M...ton%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.

[kenndapp]

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?

[KhanRad]

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.

[wrinkles]

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.

[DocGKR]

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.

[C4IGrant]

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