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:
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:
Gives a whole new meaning to “that’ll leave a mark,” doesn’t it?
Get the Book
The Writer’s Guide to Weapons: A Practical Reference for Using Firearms and Knives in Fiction (Writer’s Digest Books) comes with everything but the ammo. Pick up a print or digital copy from these fine retailers: