The reason I'm posting this here is because the test will be documented and posted here in Tactical Gear in another thread. 

I've got some IIIa soft armor I'm planning on testing. My question is which backing material to use? Trying to do this with materials I already have on hand. Those being:

• Sand
• Water/milk jugs
• Newspaper
• Very dense (still kinda squishy/pliable, but it's pretty tough stuff) closed cell packing foam in block form
• Jello

Which of these would be best? I was thinking of wet sand in a jug or bag, or wetpack (wet newspaper) stuffed in a jug. I know the "proper" backing material is Roma Plastilina #1 clay but I don't feel like spending the money on it, so unless someone wants to send me some or pay for it (which I'm perfectly open to ) the backing will likely be one of the above unless I can think of something else to try. 

One last thing, whats the best way to secure the armor panel to the backing material? Should I tape it down or just let it rest on the backing? I image taping it at least lightly is the way to go (to simulate being strapped to your body) but I wanted a second opinion. I've got everything from scotch tape to Gorilla tape.
For those wondering, the test will be conducted for sure with some flavor of .22lr, 9mm 115gr FMJ, and .327 Federal Mag. 100gr soft points. .380 may get thrown in, and perhaps I'll throw some buckshot at it at the end. Don't really have anything else to test with...

Clay works good.

If it's just for fun jello sounds like a fun backstopper. When I test I use some packing tape to hold the plate on the clay.

Yes, but clay = me spending money. The other stuff I already have and in a disposable form, I.E. it's basically free. 

It's kinda for fun, kinda serious. It's some armor made by a guy on Ebay. He sells shit loads of it. The only test I've ever seen of it was one guy on Youtube and his account has disappeared along with his videos, so I'm setting out to test it myself. I can tell you it stopped what he shot it with but can't remember what all it was, I remember .40 S&W for sure. He shot it placed up against some ballistic gel but didn't have it taped down IIRC. 

It's cheap (I'm talking dirt ass cheap for soft IIIa armor) which is why I'm able to test it and why I really want it to work. I'm testing a 6"x6" square that he sells for $18 shipped. 

Gallon milk jug with the top left off with a mix of sand and loam for some deflection.

Strap it to whatever you decided to mount it to.  In the lab, the panel is inside of a light weight basic carrier and then large 2" elastic straps are used to hold it onto the clay.  Three lefty-right, two uppie-downie.  It's strapped on pretty tightly.


CHRIS

Water jugs work, but the backface generally will split the jugs, and then the panels will get wet. If you don't want to buy a non hardening clay (it's not cheap), then I'd default to using sand in water jugs. Just note that in the tests, that and "backface" you may get could be skewed. 

You got a link to the armor?

Got it, thanks. I don't have any straps I'm willing to sacrifice so it'll get taped down good for each shot. 

Thanks. Yeah, I know I won't be able to get a BFD measurement without using clay. This is mostly just to prove whether or not this guys armor works at all.

Link to the guys ebay store. I actually had him do some custom work for me since he's so cheap. Came out good. But I've had a bit of a nagging sensation to test his stuff and see if it really does work. 

I don't doubt that it'll stop something, it's more a matter of if it will perform to the claimed IIIa specs. His inserts are all 28 layers of "Kevlar" (doesn't specify which type) wrapped up in 2 extra layers which are glued together. I can see through the layers some diamond shaped cross stitching. I'll be sure to thoroughly dissect and photograph the inserts construction. 

FWIW he also repurposes retired inserts by making carriers himself for them. From what I've seen all the carriers he sells are made by him. 

I've bought some of his stuff, didn't know he did custom work. Super cheap.

Yeah, I have some thigh rigs made to take ballistic inserts but they aren't sold anymore so I asked if he'd make me some custom inserts. Told him I'd draw up a diagram and to just cut them to that shape. He said send it so I did. He quoted it, I accepted, and he made them. Done.