Shooting Myth: Knockdown Power

Knockdown [nok-doun]
adjective

  1. Capable of knocking something down; overwhelming; irresistible: a knockdown blow.
  2. Internet lore referring to the ability of large guns like .45’s and shotguns to literally knock people off their feet.

Last week, I wrote about Ten Examples of the Internet’s Worst Gun Advice, and that created quite the discussion! A lot of the conversation stuck on the issues related to knockdown power. Some are still convinced that a shotgun will knock someone backwards, through a plate-glass window or into the next county. Others got hung up on related issues, like stopping power or lethality.

I decided that this was a great excuse to go to the shooting range and do silly things, so let’s talk about the literal definition of knockdown power. I don’t mean stopping power, or lethality or capability to cause damage. Those things are pretty clear concepts. I mean literal knockdown power. Can a projectile fired from a commonly available firearm literally knock someone off their feet? We aimed to find out – and brought a video camera along to document the experiment. There’s a link to the video towards the end of this article.

Testing the Knockdown Power myth with a 50 pound bag of sand and a bulletproof vest.

Testing the Knockdown Power myth with a 50 pound bag of sand and a bulletproof vest.

Since I couldn’t find any volunteers to get “knocked down” I decided to use a 50 pound bag of sand as a stand-in substitute. Yes, I’m the adventurous sort. I’m stacking the deck in favor of the knockdown power myth. Even though an average evil dude is likely to weigh 150 pounds or more, we’re going to see what various projectiles do to an object that weighs just 50 pounds.

One more thing. There was a lot of discussion in the comments last week about kinetic energy, bullets passing through targets and the concept of energy dumps. So to make sure that our Sandbag Stanley absorbed all the gusto and enthusiasm that each round had to offer, we clothed him in a bulletproof vest. It’s for science after all.

Read the rest at OutdoorHub!

What Happens When You Shoot A Bullet Proof Vest? We Test Engarde Body Armor

Did any of these penetrate the Engarde Body Armor? Read on to see...

Did any of these penetrate the Engarde Body Armor? Read on to find out…

Is he a plastic Saddam Hussein or a 1970s Porn Star? We don't know, but either way he's protected with Engarde Body Armor.

Is he a plastic Saddam Hussein or a 1970s Porn Star? We don’t know, but either way he’s protected with Engarde Body Armor.

Did I mention we’re giving away a set of FREE body armor? Thanks to the good folks at Engarde, we are. You can get full contest details here, but in short, it’s simple to win. Just like our Facebook page and you’re entered.

The Engarde folks sent us two sets of body armor. One to give away and the other to shoot to pieces. After all, we wouldn’t want to give our readers any untested gear, right?

Since we couldn’t find any willing, and breathing, human volunteers, we dressed up Plastic Saddam with some Engarde Exterior Body Armor and took him to the range. Most of the folks at our local shooting range thought he was a 1970s era porn star, but we knew he was a bona-fide, genuine, evil dictator that really needed to be shot. Either way, with that hairdo and cheesy mustache, dispensing of him was a service to humanity.

A quick look at Engarde Body Armor

This specific model is similar to the Engarde Patrol. It’s an external setup with soft panels that are inserted into the carrier front and rear. The sides overlap so there is full coverage around the body. The carrier also features external pockets which are sized to house optional ceramic plates for protection against rifle and machine gun rounds. The soft panels included with the system are intended to stop pistol calibers only.

The Dyneema soft panels fill the entire space of the carrier. Soft panels insert via a full-width Velcro closure across the bottom of the vest.

The Dyneema soft panels fill the entire space of the carrier. Soft panels insert via a full-width Velcro closure across the bottom of the vest.

The material inside the panels is genuine Dyneema SB-21. While I didn’t count exactly, there are about 40 layers of Dyneema material in each ballistic soft panel. Each layer of Dyneema feels somewhat like a cross between wax paper and plastic tarp material. It’s got a slick and waxy feel to it with a “crinkly” texture. And it’s very, very lightweight.

This specific product is rated National Institute of Justice (NIJ) IIIa. The simple description of the NIJ IIIa rating is that it’s intended to stop most pistol rounds in calibers ranging from .32 through .44 Magnum. Previous certification definitions like NIJ II would not necessarily stop .357 Sig full metal jacket or hard jacketed .44 magnum rounds.

I won’t go into NIJ specifications here, but levels are carefully documented for different type of projectiles, i.e. full metal jacket, moving at specific maximum velocities.

Strength is achieved via layering. While I didn't count, there must have been at least 50 layers of Dyneema material on each side.

Strength is achieved via layering. While I didn’t count, there must have been about 40 layers of Dyneema material on each side.

The vest we tested is rated for up to four straight-on, zero-degree angle hits per panel and two thirty-degree oblique hits. As I did not want to worry about deflected shots, I only tested zero-degree deflection scenarios, so perfect performance would be defined by four stops per panel.

Did it stop bullets?

For no specific reason other than some weird OCD tendency, I decided to shoot the front of the vest with smaller caliber pistol rounds including .32 ACP, 9mm and .357 Sig. The back vest panel I reserved for the slow and fat heavies like .40 S&W, .45 ACP and .44 Magnum.

After being shot several times, the Engarde vest puffed up like Michael Moore at free pizza night at CiCi's. The layers of Dyneema separate while absorbing energy of the incoming projectiles.

After being shot several times, the Engarde vest puffed up like Michael Moore at free pizza night at CiCi’s. The layers of Dyneema separate while absorbing energy of the incoming projectiles.

Being me, I was a bit curious about two things. First, I wanted to verify the vest met manufacturer claims. Would it stop handgun projectiles in the rated bullet type and velocity parameters? Second, could I exceed those parameters and possibly make it break? And by “break” I mean at what point would a round be able to penetrate the vest?

During the vest destruction, I was careful to move shot placement around so that no two impacts were closer than three or four inches to each other.

So let’s take a closer look at results by ammunition type.

.32 ACP

Just for variety, I shot the vest with three different .32 ACP rounds with a Walther PP: Fiocchi 73 grain full metal jacket, Hornady 60 grain XTP and Cor-Bon 60 grain JHP. I thought perhaps the small diameter round nose of a .32 ACP FMJ might stand a better chance of sneaking through the vest undetected so to speak.

A .32 FMJ (left) and .32 hollow point (right)

A Fiocchi .32 FMJ (left) and Cor-Bon .32 jacketed hollow point (right)

No such luck.

This .32 ACP hollow point flattened to about 20% of its original length. And yes, it stopped immediately on impact - I did not remove any layers of Dyneema in this photo.

This Hornady .32 ACP hollow point flattened to about 20% of its original length. And yes, it stopped immediately on impact – I did not remove any layers of Dyneema in this photo.

The full metal jacket projectile flattened like a spoon, one hollow point somewhat self-destructed and the other flattened to about .125 inches top to bottom. If you’re covered head to toe in this material, and attacked by a horde of Walther PPK wielding evil dudes, you don’t have much to worry about, except bruises.

9mm

Since I was feeling ornery, I decided to use 9mm ammunition that was designed to penetrate – Hornady’s Critical Duty. It’s a 135 grain 9mm load that is designed not to expand as easily as the standard Critical Defense load. It’s intended for law enforcement use where barriers like car doors and windshields might be encountered. And it travels at about 1,115 feet per second, so considering the heavier than average weight for 9mm, it’s moving right along. I’ve even tested this load against a giant pile of BS – The New York Times – and it performed superbly. To make sure velocity was up to par, I shot it from a Glock 17 Gen 4.

This Hornady Critical Duty round hit within ½ inch of the edges, yet still was stopped in the first five to eight layers (of 40)

This Hornady Critical Duty round hit within ½ inch of the edge, yet still was stopped in the first five to eight layers (of 40) of Dyneema

Again, no luck. And I noticed something really interesting that would appear a few shots later with the .357 Sig testing. All giddy with excitement and curiosity, I yanked one of my shots a bit off target, so it hit within ½ inch of the right hand side of the vest. I expected the projectile to take the path of least resistance and deflect away from the vest altogether. Contrary to my assumption, the round traveled inwards towards the center of the best and got tangled up in the Dyneema material. It’s almost as if the edge hit encountered more resistance than less.

.357 Sig

Keep in mind, by this point, the front panel had been shot 5 times, or one more than it’s rating. As the panels are shot, the Dyneema sheets start to separate as projectiles dump energy into the vest. As the layers separate, penetration is more likely.

Although I didn’t really plan to be unfair from the start, that’s kind of what happened. Shots six through eight, or double the vests rated capacity, were done with a smoking hot round – the .357 Sig. The projectiles are the same diameter as 9mm at .355 inches, but velocity is cranked way up. The two rounds I shot, Georgia Arms Gold Dot and Winchester PDX1 Defender both use 125 grain bonded projectiles at 1,400 and 1,350 feet per second, respectively. I used a Glock 31 with a 4 ½ inch barrel to get every possible bit of velocity advantage.

The .357 Sig Georgia Arms Gold Dot flattened completely - even though it was the 6th shot at the front vest panel - two over rated capacity.

The .357 Sig Georgia Arms Gold Dot flattened completely – even though it was the 6th shot at the front vest panel – two over rated capacity.

Shot six was the Georgia Arms Gold dot. It flattened completely into a nickel-sized blob of lead. Like the previous projectiles, it was stopped cold in the first ten layers of Dyneema material.

Next up were shots seven and eight, which exactly doubled rated capacity of the vest. These were both Winchester PDX1 Defender .357 Sig rounds. The seventh shot didn’t flatten, but tumbled and got caught up about half way through the vest panel – another complete stop.

The eight shot, or double the rated capacity of the vest, passed through the front panel, but didn't even penetrate the mesh of the back panel. It was clearly out of gas.

The eight shot, or double the rated capacity of the vest, passed through the front panel, but didn’t even penetrate the mesh of the back panel. It was clearly out of gas.

The eight shot found how much punishment the vest could take, as it passed through and was immediately stopped by the back panel. At this point, having absorbed eight hits, the vest was done. It had blimped up to approximately eight inches thick as the panels expanded more and more with each subsequent hit.

As the rated standards call for up to four “straight on” hits, I would certainly say it did it’s job absorbing eight – three of which were from very hot .357 Sig rounds. Now let’s look at the back panel, where I tested the “heavier” and larger caliber rounds.

.40 Smith & Wesson

I had no doubt the Engarde vest would stop a relatively slow 180 grain .40 S&W projectile, so I decided to try a lighter weight and higher velocity round – the Speer Gold Dot 155 grain bonded hollow point. I clocked this specific round at 1,168 feet per second from a Beretta PX4 Storm.

Both the Hornady Critical Defense 125 grain FTX .357 Magnum (left) and Speer Gold Dot 155 grain .40 S&W (right) were stopped cold.

Both the Hornady Critical Defense 125 grain FTX .357 Magnum (left) and Speer Gold Dot 155 grain .40 S&W (right) were stopped cold.

I’ll let you guess what happened. With the first hit on a fresh Engarde panel, I observed full “splat” with virtually no penetration into the vest.

.357 Magnum

Next up was .357 Magnum shot from a Ruger LCR. I used Hornady’s Critical Defense 125 grain FTX round. As expected, the second shot on the fresh back panel yielded the same result – a flattened bullet caught in the first several layers of material.

.45 ACP

Getting bored by all these stopped bullets, I decided to try a couple of different things. First, I had to try one of my favorite carry loads for my Springfield Armory TRP 1911Remington Golden Saber 185 grain +P. It’s a jacketed hollow point that I’ve choreographed at 1,167 feet per second from this particular pistol.

It penetrated exactly two of the 40 Dyneema layers before flattening completely. Yes, two.

So it was time to try a different option. I recently picked up a box of DoubleTap .45 ACP +P hard cast ammunition. It features a solid lead, semi-wadcutter projectile that’s designed for hunting thick-skinned critters like wild boar. Surely this would do something dramatic right? It was also the fourth shot at the back panel – the last shot within the performance rating of the vest.

Both the Hornady Critical Defense 125 grain FTX .357 Magnum (left) and Speer Gold Dot 155 grain .40 S&W (right) were stopped cold.

The DoubleTap 255 grain hard cast and Remington Golden Saber 185 grain +P .45 ACP projectiles.

Well, the 255 grain hard cast projectile did manage to penetrate a bit further. One layer. That one passed through two and stopped at the third, making a small tear in layer three. Only 37 more layers and it would have gone right through.

.44 Magnum

I know, there aren’t many .44 Magnums on the streets, so testing body armor against that isn’t really practical. But it did sound entertaining. So I dug out a box of Magtech 240 grain semi-jacketed soft point ammunition and launched one from a Ruger Super Blackhawk.

.44 Magnum versus Engarde Body Armor

.44 Magnum versus Engarde Body Armor

The result? Yet another deformed bullet, this one caught in the first four layers of the vest’s material. Add “magnum” to the mix and you get one more layer of penetration. Only 36 to go!

Closing Arguments

This was enlightening and a little bit shocking. After shooting each side of the vest, I cut it open to examine the results. As described earlier, the Dyneema material somewhat resembles wax paper. Heavier and stiffer, but not something you would think capable of stopping a bullet. Even though I understand the science behind it, it’s still mind-boggling when you feel how light the panels are.

This vest worked beyond what is advertised. I had to shoot the front panel to double the specification before it failed. The rear panel was shot five times – all with some insanely powerful handgun loads and never failed.

A slew of really messed up bullets.

A slew of really messed up bullets.

There was no deflection. All bullets were caught up in the material and stopped cold. Two shots hit on the very edge of the vest, yet were still trapped.

Watching the target stand and vest “jump” with each shot, I quickly decided I would prefer never to be shot, vest or not. While these have saved hundreds and maybe thousands of lives, getting hit with a supersonic projectile will still leave a mark. Ouch.

The model tested, identical to the one we’re giving away, is a great “emergency” option for civilian use. It slips over your head, outside of your clothing, and can be put on in seconds. Engarde makes lots of other models with some designed to be concealed, so check them out.

Don’t forget, we’re giving an identical set to this one away free! All you have to do is like our Facebook page. Or you can get full details here.

Did you like this?

Then be sure to check out our latest book, The Rookie’s Guide to Guns and Shooting, Handgun Edition. It’s available in print and Kindle format at Amazon:

The Rookie's Guide to Guns and Shooting, Handgun Edition

The Rookie’s Guide to Guns and Shooting, Handgun Edition

Want Free Body Armor From Engarde USA?

Hey folks, I’ve got some exciting news that may cheer you up in these troubled economic times. Great, now I sound like a G. Gordon Liddy commercial…

The good folks at Engarde USA donated a free set of body armor for us to give to one of our lucky readers. Yes, that’s right. Free. No charge. And it’s not even used! Just kidding… but seriously, it is new in the box. And it’s never been shot at. If you win, it’s our recommendation that you try to avoid getting it shot at also.

Win this Engarde USA body armor. A $625 value, it can be yours just for sharing a little "Like" on your Facebook page.

Win this Engarde USA body armor. A $625 value, it can be yours just for a little “Like” on our Facebook page.

We’ve actually got a second identical set of Engarde Body Armor that we’re going to shoot at with all sorts of pistol calibers. So you can see exactly what you’re getting and how it performs. Look for a separate review article here in the next week.

But, just to tide you over, here are the basic features:

  • External configuration designed to wear over your shirt.
  • The carrier fully encloses front and back panels that overlap on the sides.
  • The panels are constructed from Dyneema SB-21. You can read more about that here, but for now, know that it’s designed to stop most pistol rounds.
  • Separate pockets allow insertion of ceramic plates to help stop rifle or machine gun rounds. Ballistic plates are not included in this giveaway, but you can buy them from Engarde USA.
  • Generous hook and loop panels allow attachment of gear on the exterior – front and back.
  • The carrier features hook and loop straps over the shoulders and around the sides for a perfect fit.
  • The interior features mesh construction to help keep you cool and comfortable.
  • The carrier is navy blue.

This is an incredibly awesome opportunity! The Engarde USA armor we’re giving away retails at $625! Yes, six hundred and twenty five dollars! 

How to win:

  • Like our Facebook page.
  • Yes, that’s it. No catches. Nor do you have to attend a brief seminar educating you on vacation property investments in the swamps lowcountry of South Carolina.
  • We’ll fire up the Google machine and use Random to pick the winner from all of our followers on Saturday November 23rd. So, instead of going shopping after Thanksgiving, make sure to get on Facebook for a minute and like My Gun Culture.
  • If you already like our Facebook page, you’ve already entered! And thanks for checking us out before this contest!

The fine print:

  • The size is large. If you win, you can choose any size you want, as long as it’s size Large. Don’t worry, be happy, the Engarde Large size fits the broadest variety of humans. I myself take an extra large, but I’ve really been enjoying the Butterscotch Krimpets recently. Sorry, no substitutions. I have one set here, in the box, waiting for you, but it’s a size large.
  • The color is Navy Blue.
  • State laws. It’s up to you to make sure there are no stupid laws in the place of your residence that would prohibit me from sending this to you. If your laws won’t allow you to win, we have to pass you by and go to the runner-up. Sorry, no substitutes or cash equivalents. Write your congress-critter and get the laws fixed so you can win next time.
  • We’ll post the winner on our Facebook page. Depending on your specific Facebook privacy settings, we may not be able to message you, so it’s up to you to check our page to see if you won. If a week goes by and we can’t contact you, we’re going to the next name generated by Random.
  • That’s about it. We’re going to keep this pretty simple. Because we believe in insane practicality.

While you’re waiting to win, why don’t you check out our latest books, available in print and eBook format. They’re insanely practical too.

The Rookie's Guide to Guns and Shooting, Handgun Edition

The Rookie’s Guide to Guns and Shooting, Handgun Edition

Now available in print! The Insanely Practical Guide to Gun Holsters

Now available in print! The Insanely Practical Guide to Gun Holsters

 

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