BIT: DIY BP armor plate (update) rnd 2 test

[Precision]

pics from test III

mk iii before.v2.jpg

Front view of 7.62x39 FMJ. This defeated our last attempt.

7.62x39 fmj.v2.jpg

We defeated it this time. Defeated it bad.

7.62x39 jacket.v2.jpg

[Precision]

The blow out along the tile edge has to do with the way I duct taped it together this time with each row having its own encasement as well as the overwrap.

x39 rear.v2.jpg

next up was the 5.56 62gr penetrator.

556 62 gr penetrator.v2.jpg

I will save you from another perfectly clean rear picture.

next up was 7 mag with a 150gr soft point. We were not so sure about the penetration of this round being a soft point but figured it would damage the plate pretty good.

7 mag.v2.jpg

[Precision]

The 7mag got owned by the plate. It did not penetrate past the first 2 layers of porcelain. We didn't know that at the time, but it gave us hope. It did send enough shock to the back lexan to rip some of the duct tape holding it on.

7.62x54R was up next. This is 147 gr bulgarian (IIRC) but definitely steel core ammo. I have sent this through 3/4" mild steel in the past.

7.62 x 54 front.v2.jpg

It took its toll on the front, but the exciting part it the rear.



The final layer (lexan) was ripped off from the impact, more from the fact that I only put it on with one layer of duct tape. More importantly, No penetration through the last layer of tile or the lexan. The dirt filled cereal box had no damage.

[Precision]

As we had FAR surpassed our expectations, we decided to hit it with a few 3", 1 1/8 oz slugs from a 28" smooth bore shotgun.

It stopped those as well. Two of the slugs were poorly aimed by the gunner and just glanced the bottom of the plate. The third slug hit the most vulnerable part of the plate. see the pic.
We know better than to do this with the steel but it was quick and easy for testing purposes.

First picture - forensic peeling away. removing the last layer of porcelain and the second layer of steel revealed this from the 7.62x54 on the first layer of steel.

7.62x54vs1stplate.v2.jpg

Our good news was on the second plate of steel there was no penetration.

First plate when completely removed from the plate.

1st steel plate fail.v2.jpg

The slug that got a good hit, hit between the two plates and just above where the 7.62x39 FMJ impacted. Considering the mass of the slug, I was impressed. I don't think it would have made it through a solid piece of steel.

here is the second plate once completely removed.

2nd steel plate forensics.v2.jpg

The dent at the gap is the slug. the dent near the bottom is the 7.62x54.

[Precision]

Last but not least, here is a picture of the steel core from the 7.62x54R after we dug through the remains of the plate.

7.62x54 steel core.v2.jpg

So we learned a few things with the mk III testing.

porcelain is much harder and much better than ceramic tile

Separating the tile into double layers with a layer of steel in between helps to preserve the deeper layers of tile, which greatly decreases penetration.

Thicker steel works way better, both as a penetration reducer and as a tile saver.

Duct tape is a limiting factor in keeping the layers together. We need a better method of securing the materials together.

to reduce lateral tile breakage there needs to be a 1/8" gap between tiles. touching causes lots of lateral tile shattering.

Cheap Lowes plate steel (1020 high carbon) is brinell 100ish. We need to get some 8620 or better and get into the 300 brinell range.

2 5/8" of our concoction will stop most anything you will face.

[Precision]

yeah, AR plate is what they make the better sil targets out of.

True. The son wants some 1/4" AR 500 with 2 layers of tile over the front. I agree, that should stop all the same stuff we stopped today and the tile will save the AR500 as well as dissipate some of the sledgehammer effect. Although much thinner and an all around better way to go, it goes beyond the concept of DIY chest plates that can be made from items easily scavenged in the neighborhood.

His method will create a 10x12 plate that weighs in at about 10# and be about 1" thick. An improvement in both weight and thickness to version III. Version III came in at about 2 5/8" thick and about 9.5#'s for a 9"x6" slab. It will also significantly raise the cost. I had $16-18 in that plate (mostly in the steel). He is likely looking at north of $40 for sheet of steel before shipping costs on AR 500.

Either way it has been fun. Testing the AR500 with tile on the front will be cool too.

[Aglifter]

Pretty sure 1/4 AR500 will stop most rounds.

My plate rack has AR500 for the targets - pretty sure they are rated indefinitely for pistol, and~2000 rounds of 223...

[Precision]

Start rotating your materials on a bias between layers to produce interference patterns rather than convergence patterns.

I thought of that today when I was cutting up new tile for the mk IV test. I am also going with a different size tile on layer one vs layer two to help reduce the convergence effect as well.

This is fun, and hopefully will never be practical / useful knowledge.

[Precision]

Pretty sure 1/4 AR500 will stop most rounds.

My plate rack has AR500 for the targets - pretty sure they are rated indefinitely for pistol, and~2000 rounds of 223...

I think most of the targets are 3/8" steel. I know some of the high power rated ones are 1/2"

AR 500 on targets is a little different in that they are mounted on a hanging platform and this allows the steel to deflect dramatically. This would be lowered by having the plate against your chest, so the penetration would be greater, or at least that makes common sense to me. Not to mention that your chest now absorbed that deflection swing.

I may be wrong, but I think the tile helps to absorb some of that energy as well as increase the meplat of the bullet, thus making the steel more effective when it is struck.

[HTRN]

Pretty sure 1/4 AR500 will stop most rounds.

Wideners sells a bunch of AR500 targets for the DIY crowd(IE, only buy what you need, the rest you fab yourself.
They sell 3/16" for rimfire, and 3/8" and 1/2" for centerfire rifle @ distances < 100yds.