Musings on the 12-18" rule


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Skribs
February 25, 2014, 09:39 PM
Anyone familiar with the 1986 FBI Miami shootout and the follow-up research into the failures to stop the bad guys knows that the FBI recommends a minimum of 12 inches and maximum of 18 inches of penetration in a duty load. The idea is that while a bullet hitting the target straight on might only need a few inches to reach the vitals, if the bullet has to travel at an oblique angle and/or if it has to pass through an arm first, you are going to need something that can go the recommended 12-18”.

Many self defense enthusiasts (like me) have latched onto this number as the golden rule. If it’s good enough for FBI duty loads, it’s good enough for self defense loads, right? Well, in theory yes. The FBI shooting a perp has the same goal as a civilian shooting an assailant – to stop the bad guy. However, I was watching a Youtube video where the guy was testing various types of ammo to find those which worked “best” in his handgun, and he automatically rejected anything that went over 18” in gel, because it “overpenetrated.” This got me thinking…

The way I see it, you have two extreme situations described above. Scenario A is when the bad guy is squared off against you. His arms aren’t in the way, his chest is at a 90 degree angle across your bore, and the bullet only needs a couple inches to hit the vitals. Scenario B is the worst case scenario the FBI looked at, where you need 12 inches or more. A bullet that goes 15” in gel is just perfect for scenario B, but will greatly overpenetrate in scenario A.

This is the justification some people have for going with underpenetrating ammo, and I can see their point. My point is, if I have a round that will go 20”, it might “overpenetrate” in scenario B, but any round deemed worthy will overpenetrate in scenario A, and any round will vastly overpenetrate on a miss (which it is a common assumption you will have 30% accuracy in a shootout).

You can draw your conclusions from that if you wish. I personally say more than 12” is good, under 18” is fine, but not necessary. However, this train of thought, and watching some more ballistics gel videos, led me to another train of thought on the same subject. I realize bringing up underpenetration vs. overpenetration is a forum taboo, so I’ll make up for that by bringing up 2 more:
Rifle vs. Shotgun vs. Pistol
Buck-and-Ball (and other similar gimmicks)

Let’s look at some common wound tract paths (that I quickly drew in Paint just to give you an idea of what I’m thinking about):

http://i61.tinypic.com/iohy1i.jpg

Pistol
The pistol wound tract is likely from a JHP round designed to meet FBI specs in at least one barrel length. Chances are it is something like a 9mm bullet expanded to 0.5” or a .45 expanded to 0.65”, or something in between. Maybe it expanded more and penetrated less, or maybe it failed to expand and poked all the way through.

The important thing is that from just after the start until it stops, the JHP round is a consistent width. You get that 0.5” hole from start to finish. In scenario A or scenario B you will have a 0.5” hole through the vitals (if you hit the vitals). The hole isn’t going to be very big anywhere, but pistols are a compromise.

The other big benefit to pistol rounds (if fired from a long gun) is follow-up shots. Pistol rounds do the job for very little recoil on the shooter, meaning follow-up shots are quick and easy.

Rifle
The wound tract from a common home defense rifle with high-velocity ammo is going to look like a snake that has just eaten something much fatter than itself. You will have a small neck (bigger if the ammo takes a while to fragment or yaw) of bullet diameter, and then a HUGE wound cavity from where the round dumped its energy in yaw and/or fragmentation. That giant wound cavity will generally fall short of the 12-18” penetration mark (usually about 8-10” mark), and what you’re left with is the remainder of the bullet passing through the rest of the gel.

In scenario A, this means the rifle is absolutely devastating. If the vitals are 3-6” deep, then a wound tract that extends from 2-8” is perfect for disrupting the target’s ability to fight. You’ll have a small core with much less velocity on the way out of the massive exit hole, which will put the target down in very short order.

In scenario B, you end up with a lot of damage through the initial tissue, but your actual wound tract through the vitals is only the size of the remaining core. This may be an expanded chunk with jagged edges, or it may just be a tiny rod the size of a .22 LR bullet. Now, that tissue damage and all those open blood vessels will help slow the target down, but the actual damage to the vitals is likely going to be comparable to what you could expect from a .22 LR.

With that said, follow-up shots are an important factor as well. Chances are not every shot will need quite the penetration as the worst-case-scenario shot. People like rifles in .223 over shotguns because you can follow-up quicker, and you have a lot more in reserve in the magazine. Thus, even if you don’t get the vitals in the “sweet spot” for the rounds you’re using, you have a lot of firepower to create a cumulative effect on the target.

Shotgun
Some liken the shotgun to a submachine gun, because you get several wound tracts per trigger pull. It’s not a perfect analogy – an SMG would more likely be loaded with hollow-points, meaning a much wider wound tract. Still, the shotgun is likely to produce several deep-penetrating wound tracts of 1/3 inch or a couple dozen at ¼ inch. While each wound tract is relatively small, what you get are multiple attempts to hit the vitals per pull of the trigger.

Where the rifle’s sweet spot is near the beginning of its wound tract, I feel the shotgun gets better the further it goes in. The pellets slowly spread out, giving you more coverage to hit something important. So in scenario A you get a ragged hole through where you hit, but in scenario B you are incredibly likely to hit something important. However, I think this is much better in scenario A than the rifle is in scenario B, at the cost of greater recoil.

Special
I’m not talking about .38s and .44s here; I’m talking about the special rounds you see people offering mixed shotgun loads like buck-and-ball, or the new G2 RIP ammo. The G2 RIP, for example, has petals that penetrate about 4-5” and look like a scaled-down shotgun blast, and then a penetrating 9mm core that goes through to about 16”.

I used to look at buck-and-ball loads and say “if you need a slug, just get a slug and forego the extra recoil of the underpenetrating buckshot. If buckshot will suffice, then get rid of the slug, add several pellets of buckshot, and increase the surface area of your wound tract.” However, the different scenarios above got me thinking:

In scenario A, the penetrating core of the G2 RIP will overpenetrate, but so will any defense load. However, you get a nice wound tract through the vitals that you wouldn’t get with just a solid projectile.

In scenario B, the lesser-penetrating fragments cause superficial damage, just like a fragmenting hollowpoint (Glaser safety slug, anyone?). However, the penetrating slug continues through like an FMJ, except it doesn’t go too far.

What do these multi-depth wound tracts look like? Well, it’s not exactly the same as a rifle round, but it seems to be pretty close. You get a large wound tract in Scenario A and a smaller, stable tract through Scenario B. Like I said, I know it’s not exactly like a rifle. It’s a lot of little wound tracts that look like one big one when viewed from the side, whereas the rifle tract is big even in cross-section.

Conclusions

This is a big long post that basically is just me looking at different wound tracts and how they apply to the 12-18” rule, or how they apply in a best-case scenario. I still don’t think I would go with a multi-depth round like buck-and-ball or G2 RIP, but I can see the case being made for them.

I have to say that overall, it makes me question the effectiveness of a rifle over a shotgun or pistol round. It’s easy to say that they penetrate well and they have a giant PWC, but it’s also plain from most of the gel tests I’ve seen that in the “magic” 12-18” mark, most of the energy from the rifle round has been dumped and you’re left with the small remainder. Like I said, though, 30 in the box certainly helps make up for it.

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BSA1
February 25, 2014, 10:21 PM
There is a sizable group of LEO's and professionals that believe the infamous FBI Shooting was a result of poor tactics and preparation and the ammunition, particularly 9mm, performed exactly as designed.

The FBI choose to blame the ammunition rather than having to admit their agents screwed up. This led to the testing program that resulted in the adoption of the 10mm. 12 - 18" wound track is largely meaningless in the real world as there are too many variables.

kilibreaux
February 26, 2014, 01:28 AM
BSA1: The old saying: "If you can't impress them with knowledge, then baffle 'em with <removed>." applies to everything the FBI said, did, and caused to be done over the last 25 years.

First, the FBI guys did NOT use appropriate tactics, nor were they even remotely prepared to be in a gunfight. I know, we're not supposed to speak disrespectfully of maimed and dead LEO's but there is no other way to interpret what happened on that day.

They KNEW the bad guys were carrying at least one rifle...they should have been carrying their own.

I often read posts by those who THINK their 400 lb-ft of KE .45ACP PISTOL is equal too, or superior to a 1,200 lb-ft KE 5.56 RIFLE at close range...I EXPECT "civilians" to be cocky in their ignorance...but not law enforement.

This begs another question...the OP was very well written but I noticed it lacked something important...something MOST important to the discussion of firearms and lethal encounters...KINECTIC ENERGY! More importantly, delivered kinetic energy.

The FBI did such a masterful job of creating "smoke and mirrors" around the handgun caliber effectiveness issue that today many actually believe a .45 ACP is superior to the 10mm, .357/.41/.44 Magnum, and the 5.56x45! They THINK this because the FBI has constructed a complete sham concerning what a handgun round "should do."

Theres all this garbage about "permanent crush cavity" - when in reality living tissue simply does not respond this way bullets travelling at subsonic velocities. Ballistic gel...even "calibrated" ballistic gel does NOT approximate living tissue in any respect other than decelerating a bullet at a rate SIMILAR to what living tissue MIGHT. At the same time, the effects caused by supersonic velocities has been completely disparaged and marginalized despite what reality has proven time and again.

Two FBI guys are dead and others permanently disabled due to the effect a 55 grain, .22 caliber bullet traveling at approximately 3,000 fps creates. At close range the bullet tumbles violently on impact, creating tremendous lateral G-force cause the bullet to break in half. The two major portions then tend to travel divergent paths creating multiple wound channels with near instant total kinetic energy dump...over 1,200 lb-ft worth...MORE than a .44 Magnum fired from a long barrel. THIS is why people hit by a 5.56 drop instantly (expect in mythology world where all discussions are purely speculative because nobody seems to have actually SEEN someone hit by a 5.56 - or a .45 ACP). Rifle bullets cause "explosive" results because of one thing...kinetic energy. A .30 caliber expanding point rifle bullet, striking a human at over 2,000 fps will cause cause massive amounts of tissue destruction that have instant effect. None of this "magic" is the result of producing "permanent crush cavities."

The FBI guys carried handguns...low-power handguns to boot. The .38 spl should NEVER be anything beyond a deep concealment back-up piece which means its used in the shootout was ridiculous and pathetic.
The 9mm is a pretty decent round when loaded with REAL 9mm ammo...and just because the world "Silvertip" was used to hype the round that failed to stop one of the bad guys does NOT mean the bullet was being pushed as hard as possible...and in low-power handguns one simply MUST select, or load for themselves the most powerful ammo the gun can handle...not for practice, or blowing away hundreds of rounds on a range, but for carry...but even so, the 9mm is by no means the "be all, end all" of handgun choices.

The FBI ALMOST made the mistake of adopting a genuinely powerful caliber with the 10mm, but upon adoption they immediately specified it be no more powerful than a garden variety .45 ACP and 9mm. There was simply no point in having a 10mm case to fire a "low power" round and so S&W got to make some serious cash off the new .40 S&W which is indeed a pretty decent round...not in the "FBI loading" but in superior civilian loads.

But all this nonsense still ignores the fact that FBI agents chose to enter a rifle fight with pistols. Therefore nothing they do with regard to handguns or calibers has any impact on any future shootout UNLESS somewhere along the line they've also impressed upon their agents to carry flipping RIFLES with them...

There is no Army on Earth that sends troops into battle armed only with handguns...yet the FBI guys, on that day, intentionally got into their cars carrying handguns, not wearing body armor, and not prepared to deal with all the things that MIGHT have happened....which is why they all went down by ONE MAN with a Mini-14 .223 caliber rifle.

The truth is...though I already know it will fall mainly on deaf ears, is that handgun bullet penetration as a focal point for effectiveness is wrong. But, thanks to that being all the gov'ment ex-spurts hammering home "dogma" in the place of facts, we have entire generations of shooters who don't actually understand what "effective" really means.

Nobody but an insane person (or deluded) would go deer hunting with a 9mm or .45 ACP, yet people think said calibers are "ideal" for use against humans who are themselves large, dangerous, animals. What IS "effective" for deer hunting? 10mm (real 10mm), .41/.44 Magnum, and...the 5.56x45. The PROOF is hunters all over the country using .223 rifles to take deer...and Hogs.

Had the FBI guys been armed with M-16's the gunfight would have been over in a matter of seconds.

Had the FBI guys been armed with Glock 10mm's with Underwood ammo delivering nearly 800 lb-ft of KE the fight would have been over very quickly.

Had the FBI guys been armed with S&W M29 6" barrel revolvers stoked with 180 grain HC at 1,600 fps...any torso hit would have been a fight stopper.

Had the FBI guys been armed with S&W M500 6.5" barrel revolvers stoked with 350 grain JHP slugs delivering 2,300 lb-ft of KE, even a limb hit would have resulted in massive destruction of bone and tissue with the resultant and expected immediate stopping of further action.

The point IS...had the FBI guys been armed with HIGH POWERED weapons...whether handgun or rifle, the first hit would have ended the fight.

BTW...shotguns...as PROVED in that same fight, are WORTHLESS when firing "shot" at any distance that allows the shot charge to open up so that individual pellet energy becomes primary. A "charge" of 00 buckshot looks all bad-@$$ on paper when considering total energy, but PER PELLET energy is quite lame...on average just 150 lb-ft KE! Now, how many out there would choose a .22LR for their gunfight? Why not...choosing a shotgun for any range beyond POINT BLANK is the same thing. This is WHY shotguns have abysmal stopping reports when used "out in the open" at ranges beyond 15 yards and it only gets worse as layers of clothing are added. Choosing smaller shot sizes certainly increases "pattern density" but DECREASES true stopping power even closer. The ONLY thing to shoot from a shotgun is slugs...they will deliver substantial stopping power and will end the fight because they are DELIVERING 1,500-2,000 lb-ft of KE in a single projectile. Also, those who choose a shotgun should have proper RIFLE sights on it and actually AIM it.

With that said...which kicks less...the AR-15 or the 12 gauge? Of course the AR-15 and it can deliver ample stopping power with one shot, but it can also deliver 3-5 shots in LEO approved full auto. 3x1,200 = 3,600 lb-ft of KE...beats a 12 gauge EVERYDAY of the week! And can deliver that faster than a 12 gauge can make one followup shot.

So there it is...UNLESS the FBI chose to keep the full-powered 10mm, they were moving backward, and even so, unless they have trained their agents to UNDERSTAND the foolishness of carry low-power handguns into HIGH-POWER weapon fights...it's only a matter of time 'till it happens again.

The BEST weapon cops could carry when conducting traffic stops is to clip their 11.5" barrel AR-15 onto their SP sling when exiting the car and keep their hand on the pistol grip. Not only would such a display go a long way toward discouraging miscreants from acting, it would provide officers with weapons superior to MOST they will encounter.

Anyway, that's my crazy rant on the subject.

Skribs
February 26, 2014, 02:10 AM
I should mention, I'm looking specifically at self defense ranges. One thing about a rifle over an SMG or a shotgun is, as you brought up, range. This is one reason (not the only reason) why militaries use rifles instead of the other options. If a SMG is easily accurate to 200 yards, a shotgun (with slugs) to 100 yards, and a rifle to 500 yards...yeah, they're going to go with the rifle.

hartcreek
February 26, 2014, 02:30 AM
You simply can NOT compare a gel penetration depth to that of hitting meat and bone so the FBI test started out as crap in the first place.

stressed
February 26, 2014, 02:37 AM
I agree with a lot of what is being said in here. You can't compare gel to flesh. We all know what our favorite JHP rounds will do in gel from Youtube, but what about the real deal flesh and bone?

I plan to try all "gimmick" calibers, even the G2 in flesh and bone to see just how effective they are.

That's why I am surprised my real world flesh test was not more popular? (Link below)

Sure someone might say it's not effective because I shot the sow dead, but I put that bullet through it's body not even 2 seconds after I fired through it's head, so I can guarantee it's heart was still pumping per norm al when the bullet went through it's flesh. Pig flesh is similar to human (hell, some humans have pig valves in their hearts) and this sow was 250lbs, weight of a built large male.

Anyhow, I got 14" of penetration from the base, after going through bone (rib)

http://www.thehighroad.org/showthread.php?t=744355

vaupet
February 26, 2014, 04:00 AM
The US army knew this 75 years ago, as is shown in this WWII instructional video. http://www.youtube.com/watch?v=EuSOecA864o

A .45 from a 1911 bumps the helmet, a 30-06 goes trough a three and then pierces the helmet twice.

And last week, people in Kiev, who thought they were save behind a 2mm thick steel shield noticed the power of a good rifle round. They also found out that plastic construction workers bump caps are insufficient protection.

45_auto
February 26, 2014, 06:49 AM
The point IS...had the FBI guys been armed with HIGH POWERED weapons...whether handgun or rifle, the first hit would have ended the fight.

Yeah, that's why the bad guys (Platt and Matix) got away. The first hit from the bad guy's high-powered weapons on the FBI agents ended the fight.

Oops, didn't happen that way, did it?

Why do you believe that an FBI agent can be hit with a high powered round and keep fighting but a bad guy will stop?

Had the FBI guys been armed with M-16's the gunfight would have been over in a matter of seconds.

Had the FBI guys been armed with Glock 10mm's with Underwood ammo delivering nearly 800 lb-ft of KE the fight would have been over very quickly.

Had the FBI guys been armed with S&W M29 6" barrel revolvers stoked with 180 grain HC at 1,600 fps...any torso hit would have been a fight stopper.

Had the FBI guys been armed with S&W M500 6.5" barrel revolvers stoked with 350 grain JHP slugs delivering 2,300 lb-ft of KE, even a limb hit would have resulted in massive destruction of bone and tissue with the resultant and expected immediate stopping of further action.

The point IS...had the FBI guys been armed with HIGH POWERED weapons...whether handgun or rifle, the first hit would have ended the fight.

You're going to be very surprised if you're ever involved in a gunfight in the real world. My experience has been primarily military oriented (7.62 and 5.56), but I was also an LEO for 8 years. Why do you think that a torso hit (hard to believe ANYONE is still naive enough to believe in the old "hit in the arm from xxx will cause massive destruction and stop them") from a S&W M29 or S&W M500 will stop a fight, when my experience has been that a torso hit from even an M14 rifle (7.62 x 51, about 2500 lb-ft of KE) is not a reliable fight stopper?

You believe that a .44 Mag or .500 Mag is a better fight stopper than a 7.62 x 51 rifle? It appears that you believe that a big pistol bullet or kinetic energy is what stops a fight. You really believe that hitting someone with my Suburban at 4 MPH (around 3,000 lb-ft of KE) is going to make them stop fighting?

BSA1
February 26, 2014, 10:28 AM
Being a LEO when the infamous FBI Shooting took place I was able to attend some FBI training courses where the incident was discussed (Although not in great detail. The FBI largely did what is know as turtle up when criticized.

Basically the whole incident is a case study on how to do everything wrong. The agents knew about how violent Platt and Matix were, how heavily armed they were, how they obtained some of their weapons by killing citizens at shooting ranges and willingness to kill.

To keep the topic on track the FBI choose to put the majority of the blame a single 9mm for not penetrating deep enough into Platt's body to end the gunfight. Research later showed the bullet performed exactly as it was designed to.

"As Platt climbed out of the passenger side car window, one of Dove's 9 mm rounds hit his right upper arm and went on to penetrate his chest, stopping an inch away from his heart. The autopsy found Platt’s right lung was collapsed and his chest cavity contained 1.3 liters of blood, suggesting damage to the main blood vessels of the right lung. Of his many gunshot wounds, this first was the primary injury responsible for Platt’s eventual death."

Also note how the gunfight ended;

"[Agent] Mireles drew his .357 Magnum revolver [Model 13 3" barrel], moved parallel to the street and then directly toward Platt and Matix. Mireles fired six rounds at the suspects. The first round missed, hitting the back of the front seat. The second hit the driver's side window post and fragmented, with one small piece hitting Platt in the scalp. The third hit Matix in the face, and fragmented in two, with neither piece causing a serious wound. The fourth hit Matix in the face next to his right eye socket, travelled downward through the facial bones, into the neck, where it entered the spinal column and severed the spinal cord. The fifth hit Matix in the face, penetrated the jaw bone and neck and came to rest by the spinal column. Mireles reached the driver's side door, extended his revolver through the window, and fired his sixth shot at Platt. The bullet penetrated Platt's chest and bruised the spinal cord, ending the gunfight."

No magic 12" - 18" needed to end the gunfight just good marksmanship.

http://en.wikipedia.org/wiki/1986_FBI_Miami_shootout

REB
February 26, 2014, 11:52 AM
The 9mm round that hit Platt was good marksmanship, it would have hit his heart if it only penetrated a little more. The 115g round did perform as designed but had it penetrated more the odds are great that Platt would have been stopped much quicker. There may be nothing magic about 12" to 18" of penetration but the fact is the 115g 9mm round that hit Platt did not penetrate deep enough.

I have shot dozens of deer over the years with different calibers of handguns and I simply do not believe the hype that kinetic energy has anything do to with a hand gun terminal performance. The only things that maters is shot placement and penetration. Having said that the idea of over penetration is nonsense in almost all circumstances. Most rounds fired in a self defense situation miss the intended target anyway so you have to be aware of what is beyond your target.

gbeecher
February 26, 2014, 03:56 PM
The 9mm round that hit Platt was good marksmanship, it would have hit his heart if it only penetrated a little more. The 115g round did perform as designed but had it penetrated more the odds are great that Platt would have been stopped much quicker. There may be nothing magic about 12" to 18" of penetration but the fact is the 115g 9mm round that hit Platt did not penetrate deep enough.

I have shot dozens of deer over the years with different calibers of handguns and I simply do not believe the hype that kinetic energy has anything do to with a hand gun terminal performance. The only things that maters is shot placement and penetration. Having said that the idea of over penetration is nonsense in almost all circumstances. Most rounds fired in a self defense situation miss the intended target anyway so you have to be aware of what is beyond your target.
Ditto! Overpenetration is pc hype and nonsense. Bullets are meant to penetrate and cause damage. JHP just allows for a larger permanent wound channel. I shoot fmj mostly because it's cheaper, but I also like the added penetration. (soft point rounds for hunting, by law, in my state though) Ballistic gel is only a simulant, not the real human body. Shot placement and penetration are #1.

Skribs
February 27, 2014, 01:25 AM
The 9mm round that hit Platt was good marksmanship, it would have hit his heart if it only penetrated a little more. The 115g round did perform as designed but had it penetrated more the odds are great that Platt would have been stopped much quicker. There may be nothing magic about 12" to 18" of penetration but the fact is the 115g 9mm round that hit Platt did not penetrate deep enough.

I have shot dozens of deer over the years with different calibers of handguns and I simply do not believe the hype that kinetic energy has anything do to with a hand gun terminal performance. The only things that maters is shot placement and penetration. Having said that the idea of over penetration is nonsense in almost all circumstances. Most rounds fired in a self defense situation miss the intended target anyway so you have to be aware of what is beyond your target.

I agree with the majority of this post. I will say that shot placement and penetration are the strongest considerations, but after that there are other factors that still matter (such as recoil, wound diameter, etc), but that the two you mention are most important.

I will also say that shot placement is, for the most part, a moot point in a caliber war, unless you're talking about longer range. For your average civilian for self defense, you can assume comparable shot placement (assuming the pistol round is fired from a rifle, I understand the advantages of long gun over hand gun in that regard).

"As Platt climbed out of the passenger side car window, one of Dove's 9 mm rounds hit his right upper arm and went on to penetrate his chest, stopping an inch away from his heart. The autopsy found Platt’s right lung was collapsed and his chest cavity contained 1.3 liters of blood, suggesting damage to the main blood vessels of the right lung. Of his many gunshot wounds, this first was the primary injury responsible for Platt’s eventual death."

This is one situation that makes it apparent that "shoot to stop" and "shoot to kill" have two different meanings. You can cause terminal damage with bullets that fail to stop the attack, meaning you still get attacked and then he dies hours or days later in the hospital. That does you an injustice.

No magic 12" - 18" needed to end the gunfight just good marksmanship.

The reason the FBI says that magic number for penetration is because in this situation, he was right on the money, but the bullet didn't go far enough to hit the most important target in the chest. The other options would have been to aim for a headshot (which goes against "aim for COM" training), shout "hey, turn and face me so I can hit you head on", or move to a firing position at a better angle and hope he doesn't shoot you or shift out of alignment before you get there.

While I will agree their tactics were lacking, I will not agree that at the point in time in which the shot in question was taken, he could have done better with "better marksmanship".

herrwalther
February 27, 2014, 03:54 PM
You simply can NOT compare a gel penetration depth to that of hitting meat and bone so the FBI test started out as crap in the first place.

Ballistic gelatin is a benchmark. Nothing more. You can't expect ammo manufactures to get a cadaver every time they want to test a round, that would be vastly impractical. The point of making gelatin as similar to the density of a human body as possible was to remove as many variables as possible while still being relatively cheap to test countless rounds.

Tactics will always be under attack for someone doing something wrong. Ballistics can be done in a lab without rounds going both ways. When a better round is made, science has done its part and it is up to supervisors to enforce proper training to deliver that new round effectively.

Arizona_Mike
February 27, 2014, 06:27 PM
There is a sizable group of LEO's and professionals that believe the infamous FBI Shooting was a result of poor tactics and preparation and the ammunition, particularly 9mm, performed exactly as designed.

The FBI choose to blame the ammunition rather than having to admit their agents screwed up. This led to the testing program that resulted in the adoption of the 10mm. 12 - 18" wound track is largely meaningless in the real world as there are too many variables.
I would agree the tactics and preparation were poor but Dr. Anderson's book made it clear the the ammo performance sucked. The book made it clear that there was some pretty fine marksmanship going on too.

Mike

gym
February 27, 2014, 07:04 PM
They knew who they were dealing with and should have had AR's or AK's, and vests, in their vehicles.
Someone just screwed up, as usual. They already knew who they were at that point, they could have just let them go and caught up with them a few hours later. Or had a chopper up and just followed them until the proper team was in place. It was a bad call most of all IMO

Skribs
February 27, 2014, 07:47 PM
So...this has been an interesting discussion regarding the FBI shootout, but that was merely the prelude to my topic. I understand if you disagree with my premise (the situation A vs. situation B and where the rounds are most valuable), but does anyone have any thoughts on that part of the OP?

BSA1
February 27, 2014, 08:47 PM
As I recall the 147 gr. 9mm was a one of the results of this incident. It has fallen out if favor with LEO's in my area due to lack of expansion. The 124 gr. 9mm seems to have a good street record.

Somewhere I have a comprehensive report on the FBI shoutout. Most of the fine marksmanship was by Platt. Dang! Now this has me looking for that report.

There is a very good made for TV movie about the shoot out. Actor David Soule protrayed a very real to life role of Platt.

REB
February 28, 2014, 10:19 AM
So...this has been an interesting discussion regarding the FBI shootout, but that was merely the prelude to my topic. I understand if you disagree with my premise (the situation A vs. situation B and where the rounds are most valuable), but does anyone have any thoughts on that part of the OP?

To your question there is no such thing as over penetration especially in a handgun round. There can be a balance between expansion and penetration but penetration and shot placement is key. You can't control the situation all you can do is prepare for worse case. Even if the BG is square to you there is always the chance the bullet will have to traverse an arm before center mass. There is no magic bullet or caliber, the only shot that is most likely to stop a BG instantly is a hit to the central nervous system and then there is no guarantee.

There is nothing magical about buckshot from a shotgun like some people think. Buckshot is prone to under penetration and this fact is often overlooked. Somewhere I have a number of incident reports where a BG was hit multiple times with buckshot and failed to bring the encounter to an timely end.

You really can't compare handgun and rifle terminal performance. The biggest mistake the FBI made was taking a handgun to a rifle battle.

gbeecher
February 28, 2014, 11:33 AM
The biggest mistake the FBI made was taking a handgun to a rifle battle

Amen! How true. Once again, guns are tools - pick the right one for the job.

peacebutready
February 28, 2014, 12:12 PM
The FBI ALMOST made the mistake of adopting a genuinely powerful caliber with the 10mm, but upon adoption they immediately specified it be no more powerful than a garden variety .45 ACP and 9mm.

Had the FBI guys been armed with Glock 10mm's with Underwood ammo delivering nearly 800 lb-ft of KE the fight would have been over very quickly.

That's because they weren't able to shoot at their standards with the 10mm.

Godsgunman
February 28, 2014, 03:13 PM
I don't want to delve to deep into this other than saying that I have never liked nor trusted gelatin testing past mere entertainment purposes. It's interesting to watch and can give a "ballpark" figure however that ball park is a very very big one in my opinion. Bare gelatin and even 4-layer denim tests don't give an accurate result unless you want to see what happens if you shoot a 800 lbs blubberous whale of a human in the abdomen. To get accurate information, tests need to be run using flesh and bone because to hit the important stuff, you'll have to go through bone and sometimes a couple. Like some have stated here already, look at the effects on deer or pig and you can more readily expect such effects on human.

Skribs
February 28, 2014, 04:24 PM
Regardless of whether or not you trust ballistics gel specifically, the physics involved suggest the diagram in my OP is how these would work. The rifle round would dump its energy at the start of the wound tract, meaning once you get deeper, it hass lost its velocity and cannot produce the same size cavity.

BSA1
February 28, 2014, 05:38 PM
So here is the issue;

When is it a inch too short and a inch too far?

Rob62
February 28, 2014, 08:13 PM
When is it a inch too short and a inch too far? :uhoh: :rolleyes:

Over penetration is rarely the issue, under penetration is what causes the problems.

Regards,

Rob

eldon519
March 1, 2014, 12:30 AM
A lot of the OP is based on penetration depth in gel. If I'm not mistaken, each layer of skin is supposed to use up 3-4" of gel penetration equivalent. So 12" gel is around 8-9" penetration in a human if it doesn't exit.

Skribs
March 1, 2014, 12:39 AM
I could be wrong because it's been a while since I read it, but I think the FBI specs said that something that reaches 12-18" in gel is good, and that they considered that already.

BSA1
March 1, 2014, 09:23 AM
"When is it a inch too short and a inch too far?

Over penetration is rarely the issue, under penetration is what causes the problems."

You missed my point. A bullet is always a "inch to short" when it fails to incapacitate it's intended target regardless of it's design, distance, velocity, etc. and a "inch to far" when it over penetrates and hits a unintended object.

Tirod
March 1, 2014, 10:10 AM
The worry that overpenetration will hit an unintended target is liability thinking when a lethal threat should be the focus.

We hear this mantra chanted constantly on HD topics, "I have to choose an underpowered round because it might kill a family member or a neighbor."

Justifying inferior ammunition because of a "what if" situation in the face of a clear threat to your life is poor judgement. So is not knowing what is behind your target, too. #4 means that you understand where your bullets will go if you miss. Worrying about the final few hundred pounds of energy striking someone else is focusing on an extremely small window of incidence.

Survey YOUR house from the perspective of where you might encounter an armed intruder - it's not a 360 degree exposure to gunfire from any angle. Start at a position facing the most risky door (that analysis should get you a lot more aware,) just exactly where will the bullets go? Do you need to move to one side to get more cover or a better angle? What does that downrange option look like?

Most people repeat the concept we need to reduce overpenetration without knowing if they even have a problem area to be concerned with. They never walk the house and trace out the most likely downrange vulnerabilities.

On the street, we already see the problem in the stereotypical over staffed NY apprehension, where a perp is spotted and two dozen officers arrive simultaneously, all firing at the suicide motion of an overstressed repeat criminal. 60 rounds later, innocent passersby are being treated. A long long look at the tactical situation should be taken there, and the cost of liability suits should be the reason. What good is it to have dozens of officers firing when the reality is only one or two has the best angle to reduce stray bullets hitting the public?

Most of us aren't running to the sound of gunfire, and frankly, if we did, (school, mall, restaurant,) the number of people in the way isn't guaranteed to be high. At worst it's a hostage situation, or a small number standing in close proximity. I have to ask - if you can't shoot around them, why are you even trying? You need to back down. Lump it. It's what our LEO's are required to do when the correct tactics are being used.

Know your target and backstop, simple as that. Rule #4. The likelihood of someone else getting hit is unfortunate - it could happen, but I'm going to state it as a percentage, 95% unlikely. In that range of probability, a lot of other things are also not guaranteed, your gun functioning, the ammo firing correctly, the perp standing still long enough you can shoot, a second perp coming onto the scene, etc.

All you can do is be aware and try. Not deliberately sacrifice an option where penetration is needed - something that most civilians don't understand about military ammunition. It's not optimal to have hollow point when your enemy is wearing full battle gear and hiding behind an adobe wall. It's not optimal to shoot lower powered ineffectively penetrating ammunition when a known assailant is beating down the solid core wood door to your safe room.

Internet hysteria about overpenetration is adopting an option to fail, and covers up not knowing where you are shooting in the first place.

commonwealth109
March 1, 2014, 10:05 PM
One thing I agree with is the lack of effectiveness of any type shotgun shot over a certain distance. In fact many more LE dept's are incorporating slug usage. Having a shotgun that you can supplement buckshot with a slug if the confrontation gets over X yards is extremely useful. I'd much rather hit a perp with a 12ga slug at 60 yards than a .223 round, and more depts are training with slugs than ever. Makes sense too, its hard to run around in an engagement toting a service pistol, backup pistol, shotgun, and an AR. So given one long gun choice I'd take the shotty every time, especially if I've got buck & slugs.

eldon519
March 1, 2014, 10:14 PM
Skribs, I agree the FBI has that built in. My point is that the OP seems to be applying those gel numbers to human anatomy when they are not entirely equivalent.

Skribs
March 1, 2014, 10:19 PM
No I was just showing what I've seen in gel results. Rifle rounds you see a HUGE wound tract and penetration within the 12-18" rule, which on paper it all sounds good. However, the wound tract in the 12-18" section is not the huge tract you see in the first half.

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