There’s nothing magical about body armor (aka bulletproof vests or ballistic vests or bullet-resistant vests or any number of other names). They only protect what they cover, and they offer no guarantees. (Shutterstock photo)
TLDR: Yes. The extent of that bruise and other internal injuries depends on many factors, but it’s both possible and probable to expect damage even if the bullet doesn’t penetrate the body armor.
Question: Would a Character Shot While Wearing Body Armor Receive an Injury Even if the Bullet Didn’t Penetrate into the Body?
Crime writer and friend of the blog James Pierson wrote in recently with this question culled from his WIP:
A MAC-10 is a submachine gun that fires either 9mm or .45 caliber ammunition. (Image via Wikipedia)
My protagonist is wearing body armour, good body armour, albeit under his clothes so not the absolute, top grade, bulky stuff that SWAT teams wear. My understanding is that covert body armour is not as good as the heavier, overt sort; that covert is likely to be level IIIA at the highest.
My antagonist is hit by gunfire three times in a row by a MAC-10, but he’s hit in a part of the body covered by the vest. The bullets do not penetrate the vest.
In the movies, when someone is shot with body armour on, they’re often bruised afterwards, and maybe even have a couple cracked ribs. Sometimes they’re shown being bandaged up afterward.
Obviously it depends on how far away they are from the shooter when they’re hit, what ammunition is used, etc. But all being equal, how realistic are these movie/television portrayals? How injured might my character be after a few accurate hits to his protected torso? Would he be bruised, and if so to what extent? Might he suffer more serious injuries, such as cracked ribs? Might he need hospital treatment?
The Short Answer: Yes
The mystique around body armor continues to deflate, and this is an excellent example. Yes, James, that character can expect bruising, cracked ribs and even internal organ damage. A trip to the hospital could be in order depending on how far you want to take that.
Body armor works best when it’s taking shots one at a time. That allows for the greatest dispersal of kinetic energy across the armor. But triple that energy from three rapid-fire shots, and the body armor won’t be as effective. That’s especially true if the MAC-10 in your story is using .45 caliber ammunition (it comes in a 9mm version, too, which packs less firepower).
Long story short, yes, the movies are correct in this case.
The Long Answer: It Depends
If you’ve got an afternoon to kill and a doctorate in physics, you’ll want to check out the paper, Modeling Gunshot Bruises in Soft Body Armor with an Adaptive Fuzzy System, by Ian Lee, Bart Kosko and W. French Anderson. Since I’m assuming you don’t have a subscription to ISEE Transactions on Systems, Man and Cybernetics, Part B, I’ve included the paper here as a downloadable PDF.
Here’s the money quote:
Getting shot with a .22 caliber bullet when wearing soft body armor resembles getting hit in the chest with a 40 MPH baseball. Getting shot with a .45 caliber bullet resembles getting hit with a 90 MPH baseball.
In other words, body armor might save your life, but it won’t save you from injury. Your character might wind up looking like this guy:
In case that caption is hard to read, what you’re looking at is the bruise a police officer received after being hit by a .44 caliber bullet in his body armor. That bruising is referred to as a “backface signature.” (Image via Modeling Gunshot Bruises in Soft Body Armor with an Adaptive Fuzzy System, Part B)
Gives a whole new meaning to “that’ll leave a mark,” doesn’t it?
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A good topic for authors, Ben! Lemme remember that IIIa (armor classification) means the armor will protect against a knife attack or a handgun bullet being shot at oneself, but the armor is clearly labeled NOT ENOUGH for rifle bullets or assault rifle slugs? Plus the classic vest comes with a manual saying one must replace the precious gear after being hit once, safety precaution. Vaguely like that.
A coincidence I remember: Shooting the Jelly. Our TV documentarists have found their love for that jelly which has the same consistency as human tissue (our body). Those blocks of it can give transparency to how deep a bullet penetrates & how the wound-channel looks (torn tissue, rarely just the hole), well YOU know. Thank you, Ben. (And please delete this, if superfluous or unwelcome). 😉
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That Jelly is known as “ballistic gelatin,” and it’s best used for profiling the way a projectile acts upon impact. You can make a batch at home, too:
http://www.instructables.com/id/Ballistic-Gel/
Delicious! (but not really)
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How probable is that you fall for: I knew that, just wanted to make you look an expert? 😉 Thank you, Ben!
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I’ll take it either way.
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No, Sir. You earned, and deserve, more than the stereotype, for you go beyond that and give author-examples which make the work so much easier!
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Indeed, you should replace personal armour after a single use, for safety’s sake
It’s like not crashing a car twice.
At the same time however, you can very much use the armour again. I would go as far as to say that until it begins showing abnormal deformation rates, it’s fine to use.
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Knives will be able to stab through soft armour, but won’t cut you through it. Anything sharp or pointy will make its way through soft armour pretty quick.
Correctional armour or other offerings will protect against stabbing attack however.
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Excellent info. for crime writers, Ben. Thank you once again for giving it to us straight. Always appreciate your candor.
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Great info! I’ve known two police officers (wearing body armor) who have been shot, and yes, it leaves a mark! Actually a nasty bruising. Thanks Ben for sharing this great stuff for crime writers 🙂
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Still beats the alternative!
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Actually, while we’re here, let’s build off of my last comment.
Soft armour will not provide nearly the same degree of force capture as a hard armour. Given that aramid breaks and bends to stop a projectile, you will likely experience some discomfort as the back of the panel is driven into your sternum. Still, I do reiterate: This shouldn’t cause a kill unless you’re going for an exceptional occurrence.
The FBI records no fatal deformation injuries, ever and the only one we’ve dug up is an old report of a .45/70 hitting a LEO’s II equivalent, not penetrating, but deforming in a way the examiner described as a “pencil”.
In the meantime, deformations excessive as 84mm and ~133mm have been recorded, without fatal injury.
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So how do we treat hard armour?
A challenge.
To defeat a hard plate, you’re going to need serious numbers of rifle bullets, or ludicrous numbers of pistol rounds.
Further, they will likely not show any reaction to being hit if they’re used to being struck, which can be simulated in tests such as the GIGN’s team building exercise of shooting them with a .357 in their armour.
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