Ballistic Testing of 5.56 Round Fired From SBR

Over the years, a lot of questions have been asked and a lot of theories have been offered about the performance of 5.56mm defensive ammunition out of a short-barreled AR pistol or rifle (SBR). People reference data and research that’s been done in the past to try to determine if an SBR is a viable option for home defense or patrol rifle use.

Military Ball Ammo

The fact is, most of the data that is easy to find has to do with military ball ammunition: a typical 5.56 round that’s designed to travel out of a 16- or 20-inch barrel, and designed to tumble inside the human body and usually to break at the crenulation. The tumbling causes the change in the energy hitting the bullet that causes it to break. By breaking, it gives multiple paths of wounding and damage through the human body. The tumbling also opens up the size of that wound channel.

However, this is not the way that modern home-defense or patrol-rifle ammunition is designed to work. The concern has been, it’s widely known that military ball ammo does not perform the way it’s supposed to if it’s not moving at a certain feet-per-second. And if you drop down to an eight- or 10-inch barrel, you won’t get the performance you need.

Winchester Defender Round

But with the Winchester Defender round, you are going to get the performance you’re expecting and that you need, even at a lower velocity. It doesn’t mean you have the same energy level, but you have the same dynamics of the bullet, which is what we take a look at in this video.

A .223 round is fired out of an SBR into a couple layers of heavy cotton and a ballistic gelatin block. At about three inches into the block, we see the expansion of the front of the bullet, which is what it’s designed to do. It starts breaking apart. The permanent wound area is about 1¾ inches at its widest, plus some fragments that stretch up to about seven inches into the block. The core of the bullet exits the 16-inch long gelatin block.

In short, the performance of the Winchester Defender Round out of an SBR is very impressive and you can feel confident that firing this type of .223 or 5.56 round through an AR pistol or SBR, it will still inflict the damage you need on the bad guy.

The important thing is, if you fire a 5.56 round out of an SBR, make sure you use purpose-built defensive ammunition, not military ball ammo.