There will several upcoming articles on terminal ballistics.

They will be grim.

You have been warned.

Terminal ballistics is the study of how a moving projectile (ballistic) acts as it stops (terminal…hopefully a soft target). As hunters, we use terminal ballistics to determine the effectiveness of shot placement and the functionality of the projectile we are using. The effectiveness of “hydrostatic shock” hotly debated in the sporting world. I could talk days on this subject, but for now, we’ll do a quick intro.

History

Back in the black powder days, hunters and soldiers had a simple technique for effectively killing their target with slow shooting rifles…they made a big hole. Bigger hole equals wider wound channel. Wider wound channel equals greater blood loss. Rapid blood loss equals (you guessed it) death. Then smokeless powder became commonplace. Hunters now had fast moving small caliber projectiles that had similar energy levels to large caliber black powder rifles and could expand to a large diameter.

Key term

There is a term in the gun world… “hydrostatic shock.” The scientific term is hydraulic shock, which is the momentary rising of liquid pressure. As it relates to the topic of ballistics, the projectile will impact a liquid filled target. As the projectile hits, it will displace the liquid at XX rate. The terminal effect (XX) will depend on the weight and velocity of the projectile (also known as kinetic energy- measured in Foot Pounds of Energy for our purposes), the construction of the projectile (hollow point, pointed, etc.), and the target’s thickness and density.

The two debaters

I have looked over several studies on the topic of forensic ballistics. It seems like each report conflicts the next. Hunters are on 2 sides of the fence in the shock theory. The old school primitive guys will tell you that the unnatural hole which causes blood loss will kill the target. The newer generation are firm believers in the shocking effect of hunting projectiles.

My experiences as it relates to the topic

Many moons ago, as a young man I put the crosshairs right behind a spike buck’s shoulder. I sent a 120gr hollow point from my .25-06 at about 3500fps at the perfectly broadside buck 100 yards away. I heard a sold thump indicating a good hit. The problem was, after a couple hours of searching, I couldn’t find him. Eventually, we did find one drop of blood near where he was shot. The buck managed to run about 80 yards before we finally found him in thick briars. He was hit just as I expected, a few inches behind the shoulder. Behind the shoulder is where we’re supposed to shoot deer right?

This fall, I shot a doe with my .308 and a buck with my .223. The doe was shot intentionally high in the shoulder. She was instantly killed (more of a central nervous system shot than a circulatory system shot). The buck received a 60gr Nosler Partition to the heart. He made it only 10 yards before he expired (front legs were broke also). I have many other stories just like these two.

So what do those stories have to do with anything? You will note that the two deer shot in the shoulder didn’t make it very far, while the one shot in the rib cage made it a good ways before dying. Why?

A rib cage shot offers the following resistance: skin, ribs, lungs, ribs, and skin. Lungs aren’t terribly dense by the way. A shoulder shot offers the following resistance: Skin, thick muscle tissue, femur/shoulder blade/ribs, heart/lungs, femur/shoulder blade/ribs, thick muscle tissue, and skin. You can see, that a projectile traveling through a shoulder has more resistance than a rib shot.

I have two theories to offer to you. 1- A shoulder shot has more resistance; therefore it creates more shock. 2- A shoulder shot has more resistance; therefore the projectile expands more to create a wider wound channel.

I have another theoretical question for you. There are 2 different rifles to choose from. One shoots a large, slow moving, non expanding bullet. The other shoots a ludicrously fast, rapidly fragmenting, small projectile. #1 has ultimate penetration but no shock #2 has ultimate shock, but can not penetrate. Which one is best for deer?

This is my first article on the subject. I wanted to do a basic into to get your mind turning and hopefully your eyes are a little more opened to terminal ballistics.

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