Wall Penetration & Over Penetration

[sholling]

To give credit where credit is due I found this link over on thefiringline.com and thought it interesting enough to pass on. Many of us have read boxoftruth "tests". Personally I've never been a huge fan because stacking wall board back to back tells you very little about how a round will act after penetrating a wall or two. Too much energy is transferred from sheet to sheet when stacked back to back. The poster went to the trouble of building three test walls and spaced them well apart giving a far more real world view of the how various rounds perform.

http://230grain.com/showthread.php?t=65428

[Merc1138]

Ok, first of all, the boxoftruth tests aren't sheets of drywall stacked back to back, there are indeed gaps.

Second, is it just me, or can I not find the test results in this link showing what rounds didn't penetrate the 3rd wall? That would be 6 layers of drywall. The only one I can see that didn't, was the 9mm but apparently they didn't line it up right to hit the 3rd wall, and didn't bother to re-test it. Yeah... that's real scientific "Oops, we didn't get the experiment conditions right, you want the results? Meh, we might do it later".

And third, even if the rounds didn't penetrate the third wall(I like how their article goes "just look at the speckles, that's not too bad", that still means rounds are going through two additional rooms in your home if you miss.

Actually, I'd also be more curious what happens when you do this test with say, drywall that's been attached to a wall for 10 years, or throw a wall made of that green drywall they have to use for bathrooms, kitchen tile on the other side of a wall could also be interesting.

edit: Scratch that, I glanced through it again real quickly and saw that one bounced off of the 6th drywall sheet from the 3rd wall. Their digital editing(bad paintshopping) of the drywall sheets doesn't help, and they could have had a basic chart at the bottom with a list of the rounds in one column and a list of how many sheets it went through in the other column.

[cheese]

Its nice to see more test like this and i would love to see more. These tests do seem to contradict boxotruths test but i think there is still alot to be takin from boxotruth's tests. It may not be the perfect recreation of a house type situation but at the same time it gives a pretty good way to compare penetration in a controlled environment. But either way i would like to see more test considering the results were so different.

[sholling]

Box of truth tests may as well be stacked for what little separation there is. You need a minimum of ten feet between walls to allow the projectiles to change course or slow down.

Short of building hundreds of walls and testing in a lab under controlled conditions you won't get perfect tests. You're also not going to be able to test every possible combination of walls and wall coverings. But in my opinion this is a very useful test - far more useful than what I've seen from the box.

[Merc1138]

Dude, did you miss the part where rounds are clearing the distance between what would presumably be two rooms in your home before stopping?

x = you
Y = badguy
| = double sided drywall
-- = 10 ft gap between walls that the rounds managed to cross

x--y|--|--|

The round still crossed what could be two bedrooms with family members in ALL of their test results, with most of them still managing to penetrate the third wall. That's not any better in your home. So you're still sending rounds two rooms over if you miss.

[sholling]

Anything that can penetrate a human can penetrate a couple of rooms but how much energy is left? That depends on the projectile and how it behaves. Getting hit by a 25gr bullet fragment or pellet moving barely fast enough to penetrate one more sheet of drywall is not the same as getting hit by a 230gr projectile still moving 700fps.

Beyond that is the effect on the neighbors one house over. Adding a pair of stucco outside walls and two more inside walls would be interesting but beyond the realm of this test.

[Merc1138]

Can't say I'm worried so much about the neighbors with stucco/siding on the outside of them home and mine, along with possibly a fence to add more resistance, so much as I would be the people in my home in the next room. That's what people tend to worry about when it comes to overpenetration.

[Jonathan Doe]

I wish I can show everyone some crime scene photos where the rounds penetrated from one to several walls, 9mm to 223's. But, I cannot because cases are pending.

[sholling]

Can't say I'm worried so much about the neighbors with stucco/siding on the outside of them home and mine, along with possibly a fence to add more resistance,

I worry about it. I like my neighbors. That's why I'm unlikely to grab my M1a to fend off a burglar. That 308 is likely to penetrate well into a neighbors home.

so much as I would be the people in my home in the next room. That's what people tend to worry about when it comes to overpenetration.

It's important to think about both. You are 100% responsible for that bullet 1 wall or 20 walls. The point is that each layer of drywall bleeds off energy as does each inch of travel through air. Having been hit by bird shot at a distance of 100yds or so and I can tell you that although it wasn't fun - it didn't penetrate. Air alone slowed it enough that it bounced my butt. Yup I got hit in the butt.

You're looking for absolutes my friend. Either it penetrates or it doesn't. That leaves out all of the shades of gray. Penetrated wall but not the flesh 6' behind it or penetrated the flesh but only 1/2". None desirable but a huge difference from penetrated 3 walls and all the way through the neighbor.

[Merc1138]

What does getting hit by birdshot at 100 yards have to do with rounds penetrating walls in a home? First, who has a 100 yard hall to shoot across and overpenetrate a wall. Second, like I said previously regarding siding on a house, insulation, etc. I'm less worried about the neighbors than I am of people possibly being in the next room. And you make it sound like penetrating flesh only by a half inch(still enough to injure or potentially blind someone, permanently) isn't still an issue.

This test still also assumes that the density of the drywall is all the same, there's no doors involved, and that the path is perpendicular to the walls leaving larger gaps(as opposed to cutting across a corner at an angle which would probably produce results closer to the box of truth tests) between them. You could also claim that since this test was done outdoors, the large spans between the drywall sections might possibly introduce a breeze and changing results(something not likely to occur in the home). The lack of any real use of the "Scientific Method" doesn't make this testing any more or less accurate than the boxoftruth tests, and STILL shows that 6 layers of drywall can still be penetrated across a 30 foot distance.

[SCMA-1]

The drywall tests are interesting data, but irrelevant in the home defense realm. What is more relevant is the penetration/overpenetration performance of different rounds through human bodies; that's what one has to be concerned with. If you are shooting and missing within household distances then you probably shouldn't be discharging your weapon in the first place.

SCMA-1

[sholling]

My point is that the test is useful and better than guess work and a rabbits foot. And far better than back to back wall board or minimal spacing. I can't seem to get your point other than to ignore tests unless each and every possibility imaginable can be tested and consider all hits on flesh equal. Why? What's the agenda? You obviously have one. A favored round? A pet theory that didn't fit the results?

The point of the bird shot story is that energy and pattern dissipation can be the difference between penetrating flesh and not penetrating flesh. Are you saying that's not true? Are you saying that the pattern breaks up and energy dissipates the same in near back to back spacing as in 10 feet apart? Is it just simply a box kool-aid issue? I'm confused by your argument.

The point about little energy dissipation and 100% penetration of an innocent victim vs effective energy dissipation and 1/2" of penetration should be obvious unless you're completely unconcerned with loss of life but hyper concerned about lawyers. It makes no sense. There is a huge difference between 1/2" into a chest cavity and a through and through taking out the heart and/or aorta. Are you disputing that?

[sholling]

If you are shooting and missing within household distances then you probably shouldn't be discharging your weapon in the first place.

SCMA-1

So what you're saying is that if someone is shooting at you and you're returning fire that you are so steely nerved that there is no chance that you'll miss? None at all? Darn few bad guys paint a target on their chest and hold still for you to line up the perfect shot. However if the criminals in your neighborhood are that obliging I'm happy for you.

Edit: What is also relevant and to your point is how many walls will be penetrated after a hit on a human body. But that adds the variable of where is the hit. Center mass? Arm? Hand? Lot's of variables.

[RickD6023]

Last season, the Best Defense had a great demonstration with multiple walls set up with separation to show how the walls would effect the projectiles and how many walls would be penetrated. While not in a controlled environment, the demonstation proved the point that the rounds fired will penetrate multiple walls. If I remember correctly, they shot .22, 9mm, .223, slug and bird shot. It made the point and I have since adjusted my "safe" room.

Now, what I would love to know is how the penetration is effected when a mirror is covering the wall and the wall is on an angle to the shooter.

[SCMA-1]

So what you're saying is that if someone is shooting at you and you're returning fire that you are so steely nerved that there is no chance that you'll miss? None at all? Darn few bad guys paint a target on their chest and hold still for you to line up the perfect shot. However if the criminals in your neighborhood are that obliging I'm happy for you.

Where exactly did I say that? Perhaps you have a comprehension problem? LEO's are accountable for every round that is discharged from their weapons and so are private citizens. However, LEO's and tactical teams (223 carbine is preferred) carry superbly lethal weapons and ammunition all of which are capable of penetrating multiple residential wall units. What's the difference? Training and tactics. They don't normally shoot at anyone they can't see, properly ID, have a clean shot, or engage in indiscriminate gun battles like you see in the movies and neither should you. If you still don't understand what I'm talking about, then you should educate yourself on the dynamics of close quarters confrontations as it specifically relates to HD. Better yet, take some advanced classes and see what you should and should not do in a home break-in situation because it is obvious you are not knowledgeable or experienced in the subject based on your comments.

Stay safe,

SCMA-1