Underpenetrator vs Overpenetraror

[StrawHat]

To get a better feeling for real world over vs under penetration see how it effected FBI Agents Jerry L. Dove and Benjamin P. Grogan.

Kevin

 

[MedWheeler]

I voted overpenetration, but maybe by a 51-49 percent favor. This is despite the fact that heavy clothing is rarely a factor here. I'd definitely want it in calibers less powerful than 9x18mm Makarov.

My main concern is that an attacker, if shot and not immediately incapacitated, at least knows he's shot.

 

[JTQ]

The FBI guidelines are based on "worst case" scenario, so I'll take the larger expansion at an inch or two less.

I'm pretty sure all the ballistic gel comparison tests are done at 10 feet. I'm not sure how "worst case" that may be, but you can do your own guessing whether you can expect more or less penetration depending on your expected shooting range.

I think folks also have to figure out what the likely scenario would be for them to deploy a firearm in defense of their life. Is it more or less likely for you to get into a shootout at noon on a Monday in Times Square, or on a Saturday afternoon at the Mall of the America's, or perhaps in a nearly empty parking garage late at night.

If you're in LE, a shootout in Times Square or the Mall of the America's is reasonably likely if you work those areas and the low penetrator may be a good choice. Conversely, a one on one shootout in a nearly empty parking garage is possibly the more likely scenario for the private citizen. In this case, over penetration is a little less of a concern.

Here's another one to chew on...lets's say you had to go to the Mall of the America's today and there was a 100% chance you were going to be involved in a shootout. You could choose between bringing either your 9mm Browning Hi-Power loaded with 90 gr. Super Vel ammo or your FN-FAL loaded with 168 gr. .308 rounds. Which would you choose?

 

[COLOSHOOTR]

I think a lot if the problem with penetration data is that it's grossly misunderstood by most. Ballistics gelatin is a medium used to simulate soft tissue but there is a lot inside us that is much more dense and will reduce penetration depth. Some people are heavier and have over 12" from front to back but most people who are in half way decent shape are not that thick. The most popular duty handgun round around here is the Gold Dot that averages overy 12" in gelatin. Yet, they still tend to stay in the body and not exit even in thinner individuals that are not 12" thick. The 12" minimum is a guideline to make sure you get to a depth needed to hit something to cause significant blood loss or interrupt CNS signals. Less can be a bad thing because you may not get deep enough especially if there is any barrier penetration involved. That being said, you don't need 44" of penetration either because once it's out of the body it's not doing anything to cause more damage.

 

[Cocked & Locked]

Hole Shot...in one side and out the other is my preference.

 

[Stumper]

The .380 quandary. Of course the question applies to other calibers and loads. My own "answer" is "underpenetrator" in the chamber and first in the mag followed by "overpenetrators". Good answer? I hope I never find out.

 

[buck460XVR]

Under Penetration can be an issue, just ask the FBI what they learned after the Miami shootout.

What is needed for LEOs to shoot thru car windows/doors and stop multiple threats armed with high powered rifles is a tad different than the average civilian armed with a handgun for SD/HD. Besides, there are very few folks out there where 10-12'' of penetration will not reach the vitals. While under-penetration can be an issue, so can over-penetration.

In a high adrenaline situation even at close range history has shown us that even highly trained individuals are likely to miss the intended target. This idea that a round that doesn't penetrate as much is somehow safer to bystanders just doesn't hold up in a real life situation. You have to be aware of what it beyond your target.

If your argument is that folks are more than likely to miss the BG anyway, why would we want a round that will penetrate the wall behind the BG? Do you have Superman's X-Ray vision to see thru walls and know what's behind your target there? This is the fear of most civilians when it comes to over-penetration......not what happens after the bullet exits the BGs body, but what happens to the misses in a firefight. Kinda why most folks use Buckshot in their HD shotguns as opposed to slugs, so they endanger their kids sleeping in a bedroom, two walls down. You really think that someone so hyped up on adrenaline they completely miss their target at 3 feet(the range of most SD shoots), will still have the forethought to look behind their target and make sure it is clear for hundreds of yards down the street?

Folks need to use what they are comfortable with, what they are proficient with, what works well in their firearm and what they have the most confidence in. This will be what works best for them under the stress and adrenaline of a true SD/HD scenario, not thinking if they have the right bullet for the situation. In reality, the type of bullet, we as civilians use will matter very little if at all if we survive a SD encounter. What will matter is that we have a firearm on us that we can hit what we are aiming at.

 

[ThomasT]

I'll take penetration every time. I have no faith in any FBI test and recommendations. I do my own testing.

 

[LeonCarr]

Incapacitation will occur faster with two holes in the animal than with one hole.

This applies to two legged animals and four legged animals. The faster they leak out, the faster they are no longer in motion, blood pressure drops to zero, etc, and are no longer a threat.

I know personally two people who have used shotguns loaded with 00 Buckshot to stop a threat. In both cases about half the payload (4-5 pellets) stayed inside the body and 4-5 pellets exited. In one case the person swore he heard the pellets rolling down the hallway behind the perp after he shot the perp. The pellets, even though they penetrated completely, did not have enough remaining energy to be a threat to bystanders or even stay airborne.

I want a pass through. Even with most pistol and rifle bullets after penetrating a fluid filled animal the size of a human or a game animal the remaining velocity and energy are drastically reduced. You still have to be aware of your target and what is behind it.

Just my .02,
LeonCarr

 

[REB]

What is needed for LEOs to shoot thru car windows/doors and stop multiple threats armed with high powered rifles is a tad different than the average civilian armed with a handgun for SD/HD. Besides, there are very few folks out there where 10-12'' of penetration will not reach the vitals. While under-penetration can be an issue, so can over-penetration.



If your argument is that folks are more than likely to miss the BG anyway, why would we want a round that will penetrate the wall behind the BG? Do you have Superman's X-Ray vision to see thru walls and know what's behind your target there? This is the fear of most civilians when it comes to over-penetration......not what happens after the bullet exits the BGs body, but what happens to the misses in a firefight. Kinda why most folks use Buckshot in their HD shotguns as opposed to slugs, so they endanger their kids sleeping in a bedroom, two walls down. You really think that someone so hyped up on adrenaline they completely miss their target at 3 feet(the range of most SD shoots), will still have the forethought to look behind their target and make sure it is clear for hundreds of yards down the street?

Folks need to use what they are comfortable with, what they are proficient with, what works well in their firearm and what they have the most confidence in. This will be what works best for them under the stress and adrenaline of a true SD/HD scenario, not thinking if they have the right bullet for the situation. In reality, the type of bullet, we as civilians use will matter very little if at all if we survive a SD encounter. What will matter is that we have a firearm on us that we can hit what we are aiming at.

The fact is in high stress environment you are more likely to miss. Law enforcement has tracked shooting for decades and even at close range most shots miss so the answer to your question is yes even at close range most shots are likely to miss. The NYPD traced police involved shootings for decades and under 7 yards the hit percentage was 28%. It's a whole different world between shooting at paper targets and targets that are shooting back. Most any police department will tell you there is little correlation between range proficiency and combat proficiency.

It doesn't matter if your shooting though a wall or not, when you pull that trigger it's your responsibility to know what is beyond your target whether you can see it or not. The topic of this discussion was comparing rounds that penetrate between 9 to 22 inches in gell, I assumed handgun rounds but maybe that was my mistake. Even at that extreme it's not going to make a lot of difference going through a wall.

I completely disagree with your statement that bullet choice makes no difference in a SD encounter.
If you have BG shooting at you it may make all the difference in the world. 12 inches in gell does not translate to 12 inches in a person. You take an off angle shot that has a good possibility of going through an arm first and it can easily not be enough. The only sure hit other than a head shot that is almost guaranteed to stop an attacker is to hit the spine which in most situation means complete penetration. A lung or even a heart hit may be fatal but not prevent the attacker from shooting back. 10 to 12 inches may be enough but I would rather have 16 inches or more. Why take the chance when the only argument for less penetration seems to be the idea of shooting through a target and hitting someone on the other side. I just don’t buy the argument that a round that penetrates 9inches is somehow safer than one that penetrates 18 inches. I am a big believer that that extra 9 inches of penetration could save your life.

 

[Deaf Smith]

I'm guessing you have never taken a concealed carry class or attended one of Massad Ayoob's (among others) classes.

I have (FLI-1) but I wonder how many have died cause their bullets just didn't reach far enough into their insides.

And like I said, overall most bullets miss anyway.

Deaf

 

[Captain O]

If your'e shooting anything lower-powered/smaller-diameter than 9mm Luger, you had best rely on "overpenetration". If it can't penetrate more than 20 inches, you may likely wind up on the short end of the stick.

Shot placement is king, penetration is queen. Everything else is 'angels standing on the heads of pins'.

If you don't believe me, ask the survivors of a shootout.

 

[LordDunsany]

Definitely over penetrator - two holes bleed better than one!

 

[481]

I voted for overpenetration simply because lacking the ability to reach vitals through intervening barriers (like upraised arms) is far worse than a round that exits a bad guy's body with greatly reduced aerodynamics and some fraction of its initial power.

 

[ArchAngelCD]

Just remember, you are responsible for every round you fire, including the ones that pass through a bad guy and strike an innocent. Just sayin...

 

[AlfonsDeWolf]

.22 under the chin....either. But I did vote penetrator

 

[Branko_D]

I'm not concerned about overpenetration, but I don't carry outside the house (outside walls are 25cm of concrete, so the typical 'you might shoot the neighbour' just doesn't apply short of using an anti-tank rifle - and inside walls will necessarily be penetrated by everything even remotely effective). Of course there's the risk of misses, but it's there regardless of ammo or gun.

Btw, ballistic gel can be misleading, because skin is pretty elastic and something around 200 fps is required to penetrate (which would otherwise penetrate 4-5 inches of ballistic gel). Bone can dramatically slow a bullet (or deflect it). That ball load which goes through 22" of ballistic gel might or might not produce an exit wound at all - the idea that it would penetrate clean through two people is a misunderstanding.

If the FBI considers 12" a minimum I would very much agree with that and consider that as a minimum, too.

 

[buck460XVR]

Incapacitation will occur faster with two holes in the animal than with one hole.

Definitely over penetrator - two holes bleed better than one!

This is a common misconception since two holes leaves a bigger bloodtrail. This is why when hunting big game I like a bullet/arrow that passes thru, especially when shooting from an elevated stand. But the other/exit hole does not kill any faster, just leaks more blood from the body cavity. I've shot deer with one hole and two, when hit it the lungs/heart, they die in the same amount of time/distance. Two holes just leaves a bigger mess on the forest floor. But the bullet that makes a bigger hole in the lungs/kidneys will kill it faster than a small hole. The bullet that makes a bigger hole gives a little more margin for error. It's not just about hydrostatic shock. Why does one use a broadhead that is larger or has multiple blades in it resulting in more cutting edge? For more chances of damaging something vital...to make a bigger hole. Just like when hunting, folks strive to find that "Magic Bullet" for SD/HD. There ain't but one.....the one you are most confident with. While one must use a bullet appropriate for the purpose, it still takes a shot to the vitals to kill something quickly or a hit to the CNS to incapacitate the instantly. Any bullet designed for SD/HD from a reputable manufacturer will perform as long as one hits where they need to. One is never going to be able to choose where they will need their SD weapon or when. IMHO, to use a bullet with either extreme is not a wise choice, one is better to stick with the round that is in the middle of both and shoots the most accurately, while being reliable in the firearm.

 

[2zulu1]

I want a bullet that will bust up bones commonly encountered from oblique and lateral angles against whatever sized felons.......choice is rather obvious IMO.

 

[481]

Just remember, you are responsible for every round you fire, including the ones that pass through a bad guy and strike an innocent. Just sayin...

Gee, that's never been posted on a gun forum before.

 

[TimSr]

Given the FBI/IWBA recommendation for self defense rounds being 12 to 18 inches penetration of 10% ballistic gel, which of the two following rounds would you choose to carry (assuming reliability, shootability, ect are the same)?

I am not an FBI agent, so I wouldn't make any choice of ammo based on their recommendations for their agents.

 

[cougar1717]

which of the two following rounds would you choose to carry

It depends on which point the OP is trying to make.

In the case of the .380 or another caliber that won't consistently meet the criteria, you have to ask,"Does the FBI criteria adequately describe the needs of a CCW holder?" Most CCW holders are not police and the requirements of shooting through plywood, sheetmetal, glass, et cetera are good, but not very applicable for defensive situations for which CCW holders would like to prepare.

Conversely, if the point is the other side - making the overpenetration case for carrying FMJ or other non-expanding bullets, that can be just as dangerous. As luckygunner's tests have shown in great detail, some ammo that is designed to expand doesn't always expand (or expand reliably). Some that expanded "too well" were short of 12". Some that should have expanded, but didn't, went beyond 18".

At the end of the day, 12-18" is a guideline. The human body is not made of 10% ballistic gelatin.
While it is difficult to just say "over" or "under", if I can't choose anything in the 12-18" range, IMHO, I would prefer a bullet that was consistently expanding at 10-12" to one that was not consistently expanding and extending into the 18-20" range.

 

[ArchAngelCD]

Gee, that's never been posted on a gun forum before.

True it's been said a lot but my post wasn't just to see my words in print, it was in response to all the posts that said they didn't care if the bullet exited the body or didn't care about over penetration. That is reckless and just wrong so need need for your snide post.

 

[481]

True it's been said a lot but my post wasn't just to see my words in print, it was in response to all the posts that said they didn't care if the bullet exited the body or didn't care about over penetration. That is reckless and just wrong so need need for your snide post.

Chill out. No need to take everything so personally.

 

[REB]

True it's been said a lot but my post wasn't just to see my words in print, it was in response to all the posts that said they didn't care if the bullet exited the body or didn't care about over penetration. That is reckless and just wrong so need need for your snide post.

What is reckless is assuming every round you fire is going to hit the target. Odds are they wont.