Several years ago I used to work for a large scientific organization that was right down the road from the local gun range. We used to shoot a lot of stuff on the lunch hour and after hours. I have some observations that may be useful to the self-defense shooter, home defender and others. Let’s explore how finding cover and concealment work from a materials standpoint.
First, the destructive power of a round is proportional to its velocity. The more you can slow a bullet down, the less damage it can do and the less range it has. The more you can flatten a bullet, the faster it slows down. The more you can break a bullet apart, the less damage it -may- do (there is always the “golden BB”). The smaller the parts, the easier for the individual parts to be stopped. If you can get the parts below 400 fps, odds are good the parts will not break the skin. Therefore you may not need to stop the bullet cold, but slow it down enough that it does not break the skin. You may just need to bleed off some speed.
What Stops or Slows Down Bullets?
You have metal, fibers, stone and liquids. One or a combination of any of the four may work. It depends on your application…
Maybe you want a dedicated dry-fire area or an armored safe room. How much weight you can hold and how much space you have may change what you need.
Fibers: Wood sucks at stopping bullets. Woven Kevlar works great. Fiberglass is so-so. Several layers of fiberglass with the right epoxy can be great!
Stone and liquid stone, aka concrete, work great! They are not very portable. They have thickness issues. “Baby” stones like pea gravel or sand have their place. Ceramics also fit here.
Metals: These are great for the thickness. Hard steel works best; soft steel comes next, followed by aluminum (hard and soft are blurred) and then copper. We used to shoot a lot of large electrical transformers. It was quite educational. They are layers of copper windings and mild steel. Electronics soak up a lot of bullets even from high powered rifles.
The Importance of Layers When it Comes to Cover
This leads us to a very important point! Layers! Combined layers can stop more effectively than a single layer of the same thickness — four 1/16″ thick sheets can stop more than a single 1/4″ sheet. Some of the layers may be breached, but the overall thickness has not. It may be hard for somebody to work with a single thick layer of steel, but not smaller layers. It normally takes between a 1/4″ to a 1/2″ of steel or 3/8″ to 3/4″ of aluminum to stop a bullet. Something like a metal target needs to be one solid layer, as does an active backstop. However, something like a safe room or dry fire station can use layers.
Stones are great at breaking up bullets. Patio blocks or even bathroom tiles can break up bullets. The problem is that they often break up along with the bullet. You may want to set them or glue them to some sort of backer like plywood to help hold them together. Think outside of a safe room. Works great but is one use only.
Wood and other fibers: Wood is the most common and easiest for most people to work with. It is crap for stopping bullets. I have layered as much three 3/4″ sheets of plywood and bullets fly through it. That is thicker than most wall studs by 50%. Here is why it is VERY useful. It soaks up shrapnel like a sponge. You can use it to help prevent bounce back. Now, if you were to glue some 1/8″ sheets of steel between those layers of plywood, then you really might have something.
Some time ago, I read several posts about the comfort of IWB (Inside-the-Waistband) holster and how some folks react badly or get irritated skin from the leather against their hide. In warm weather, an undergarment such as a T-shirt may not really be practical. And frankly, some folks may not wear tees. I set out to find a solution because I have sensitive skin and the leather would get hot or chafe my skin, making wearing the holster difficult and very uncomfortable. What good is a self-defense weapon if you are not wearing it right?
I starting looking at alternatives and researching some sort of backing for the holster — in this case, a few of my own hybrids and a SuperTuck Deluxe. Some suggested deer hide, moleskin or soft cloth. All these had some rather poor qualities and really did not address the issue as I would have liked. Deer hide leather had some of the same issues as the original leather. Sweat is an issue so whatever I use has to be able to dissipate sweat and still hold its softness. It has to be cool and comfortable to minimize sweat. Moleskin rolls up and exposes the adhesive, which is worse than the original leather. Plus, on a larger holster, you have to piece it on, which is not easy. Cloth just rolls up, bunches up and gets wet and uncomfortable.
Eventually, I found medical-grade sheepskin used to prevent bedsores in non-ambulatory medical patients. I researched to seek out the top grade. I finally found one on Amazon. I applied 3M 77 spray adhesive to the back of the holster and pressed a piece of sheepskin that I had cut to fit the backing of the SuperTuck. The glue held it very well and it did not move at all. I proceeded to tear it off and see if I could replace it if it got gross or did not work. I could, so I cut a new piece and glued that on. I have worn this thing for over a month now. It is unbelievably comfortable, cool to the skin and so soft that what used to be a compromise is actually fun. This has worked so well that I made the modification to all my holsters. I even had enough left over to use on my Victory Cross Country Tour motorcycle seat. It is amazing stuff even when riding in 100-degree temperatures. No hot spots. The same performance as the backing on my IWB holster. Great stuff! I thought it would be itchy, but it is not.