The Box O’ Truth #11 – Spall Liner

My friends, Goodmedicine and his son MEAD, sent me some interesting material called “multi-ply Kevlar / thermoset resin laminate sheet”.

This stuff is used as a “spall liner”.

Here’s what we could find out about spall liner.

“Recently, many manufacturers have added a spall liner to the inside of the armour, which is designed to absorb fragmentation (spallation) released from the impact of an enemy shell, protecting soldiers and equipment inside. They tend to be made from Kevlar or similar materials.”

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Goodmedicine warned me, “Do not try to cut this stuff with any of your saws, if you do you will get nothing but blue smoke and a VERY dull blade. (Don’t ask me how I know this.)”

MEAD advises that they use water-jet cutters to cut this material. It looks like a combination of fiberglass and Kevlar.

It is stiff and hard as can be. It is about 1/2 inch thick.

This gave us about 1 inch thickness.

This is the set-up. We placed four sheets on a board and cross laid 4 more the other direction.

This is the set-up. We placed four sheets on a board and cross laid 4 more the other direction.

This material is not designed to stop bullets, we are doing this to see how tough this stuff really is.

I am not trying to conduct any scientifically valid test. We are just having some fun and seeing if this stuff will stop bullets, even though that is not its primary purpose.

First a .22 LR from a pistol.

You will notice that I stood back a ways. Wasn’t sure if the bullet would bounce off the material or what.

It slightly penetrated the front of the first layer, but did not penetrate the first layer.

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Next a 9mm 115 grain Ball from my Hi-Power.

Notice the brass in the air.

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It kind of flattened out and was “squished” out of the side of the first layer.

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Next, the .40 S&W out of my Glock.

Again, notice the brass in the air.

As an aside, catching brass in the air isn’t as easy as it may seem.

I get ready and count down, “3, 2, 1, 0″. And Tman snaps the pic and I fire on “Zero”.

We catch a few good pics.

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You can see where the .40 hit and the material mangled the bullet, which was a Corbon.

Didn’t penetrate even the first layer.

We shot another .40 S&W and notice how the jacket is “squished” out of the side of the material.

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When I got home, I seperated the layers with a screwdriver (it was a difficult task) and saw what had happened.

After the first few layers, the bullet had stopped completely.

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Then I fired a round of .45 ACP Ball into the material.

As you can see, it flattened out the bullet pretty good.

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Here it is after I removed it from the Kevlar.

11-10 Time for the rifle.

Here's Tman shooting it with M-193 Ball.

Here’s Tman shooting it with M-193 Ball.

Here's the hole in the front.

Here’s the hole in the front.

Here's the exit in the back.

Here’s the exit in the back.

Lessons learned:
  1. This stuff (multi-ply Kevlar / thermoset resin laminate sheet) is tough. It stopped all pistol rounds tested.
  2. Once again, pistols are pistols and rifles are rifles. The 5.56 went through it like manure through a goose.
  3. While not designed as a “bullet stopper”, this stuff worked pretty well, at least against pistol rounds.
  4. Like Forrest says, “You never know what you’re gonna get.”
  5. Shooting stuff is fun.

Thanks to Goodmedicine and MEAD for sending me the test material. It was a fun shoot.

And thanks to Tman for the photo work.