At the fifth round, we could see the witness cardboard fall, and knew it was defeated.

Here's the back of the glass.

And here's the witness cardboard with a small hole in it.

Let's try the other sample. This one is also 20 X 20 inches, but is 1.5 inches thick and has 4 layers.

It is also rated NIJ IIIA, for Pistols.

This piece weighs 52 pounds.

I will "mistreat" this one from the beginning, by shooting it with a rifle.

It is not rated for a rifle, but let's see what happens.

First, a round of 5.56 M-193 Ball, out of my Coyote Brown AR-15.

The glass stopped the round, even though not designed for it.

We had considered trying a round of 7.62 X 51 Ball, but agreed that it would defeat the glass, and wanted to have some area to try a slug.

So, I used my Remington 870 and a Quik-Shox Slug, which has proven to be very tough in past tests.