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Of Bullets And Penetration

Of Bullets And Penetration

I was in my, ahem, reading room perusing the January copy of Shooting Illustrated when I came across an article titled,

The Terminal-Performance Triangle: Measuring Ammo Effectiveness  by Ricchard Mann.

I don’t know Mr. Mann, but I have to believe he knows what he’s talking about or he wouldn’t be writing for Shooting Illustrated. Maybe I’ll get to meet him at the NRA Annual Meetings in April. I’ve read some of his other articles and he certainly appears knowledgeable.

So, who am I to question an article by him? Well, nobody, at least not in the world of guns and shooting. I have, however, treated a good number of people who were shot over my years in EMS.

Because of that, in part I agree with Mr. Mann when he comments about the effectiveness of bullets in personal defense. Unlike on TV and in the movies, people who are shot do not generally fall down dead, let alone fly across the room as in this shoot out from “Last Man Standing.”

Look starting at about 0.41 to see what I mean,

The law of physics just don’t allow for that sort of thing, although it does look cool on the big screen.

Newton’s Third Law of Motion tells us,

For every action, there is an equal and opposite reaction.

All of which is to say that if people went flying when they were shot, the shooter would go flying in the other direction. Especially if the firearm that they are using is not an auto loader.

Back to the article,

Established on good intentions, and because of the infamous 1986 Miami shootout, the work of the FBI has driven the design and manufacture of defensive-handgun ammunition ever since. All because a single and lethal hit from a 115-grain Silvertip (oh, the irony) fired from a 9 mm did not incapacitate a bad guy fast enough. The bullet stopped in the lung, just short of the heart.

The 1986 Miami shootout was infamous because two FBI agents were killed, five others were wounded, and while the two suspects were killed, they weren’t killed or even stopped very quickly. Additionally one of the suspects had a rifle and the other had a shootgun. It took 12 shots to kill one suspect and six to kill the other.

The investigation after the shooting named inadequate stopping power as one of the reasons that it took so many shots to stop the suspects. There was also serious criticism of the tactics and lack of preparation, but I’m not going to go into that here.

As a result of the investigation and subsequent tests, the FBI decided to adopt a 10mm round and new semi automatic handguns by Smith & Wesson. The round and the guns themselves proved to be problematic and the FBI returned the guns to S&W. Meanwhile, S&W developed the .40 S&W round, which used the same bullet as the 10mm, but with a shorter case and less powder. That round was eventually adopted by the FBI for most Special Agents.

Following the lead of the FBI, many law enforcement agencies adopted the .40S S&W round and a variety of handguns to shoot it out of.

Meanwhile, back at the ammunition manufacturers, development on new bullets and powders was proceeding apace. 9mm ammunition became far more potent than it had been heretofore, as did other rounds. One of the biggest developments was in the shape, deformability, and expansion of the bullets.

When I was young, revolver ammunition was mostly .38 Special with bullets made of lead and weighing in at 158gr. That was the standard law enforcement round and the one that I learned to shoot on. As did a lot of other people. 9mm wasn’t considered a serious self defense round because it had a reputation for over penetration. The standard 9mm round had a 147gr full metal jacket bullet that came out of the barrel at high velocity. The worry was that a round that hit a person would continue through and hit anyone who happened to be behind the the intended target.

Hitting unintended targets is bad. Well, it’s worse than bad as even if the intended target is a bad guy and the shooter is defending his or her life, bad things are going to happen to the shooter if he hits an innocent person.

Which brings me to the point of Mr. Mann’s article,

It’s true, it will neither deform nor expand, and the wound cavities will be narrow. But, it’s very likely that, had the bad guy in Miami in 1986 been shot with hardball ammo from a 9 mm or .45 ACP, the round would have made it to his heart, and all this silver/magic-bullet development during the last 30 years might have never occurred. At the most-basic level, the terminal-performance triangle is made up of penetration, expansion and velocity. Hardball may not be sexy, but lack of penetration—the most-important side of that triangle—should not be a concern. And those made of silver should work just fine on werewolves.

Lack of penetration is, as he points out, bad. That being said, over penetration could well be much worse. If I’m in a self defense situation there are a few things I want to happen.

First, I want to hit the intended target.

Second, I want the round or rounds I have to fire to stop the person who is attacking me. Not necessarily to kill them, but to stop them from killing me.

Third, I don’t want the rounds to go through the intended target and off into the wild blue yonder.

Looking at the triangle, penetration is a function of velocity and bullet shape. Sufficient penetration is important, avoiding over penetration is even more so. A round with a good balance of penetration and expansion will cause enough injury to make the attacker stop.

Interestingly, Mr. Mann wrote this article for Shooting Illustrated in July of last year.

Personal-Defense Ammo: Top Picks from the Experts

Finally, you’d expect these loads—selected based on years of experience—to have something in common? I’ve tested them all, and other than their ability to penetrate at least 12 inches, they don’t. Penetration ranges from 12 to 20 inches and expansion from 1.2 to 2.2 times bullet diameter. Then there is velocity and energy variances, which range from 940 to a high of 1,240 fps, and from294 to 423 ft.-lbs., respectively.

Does this mean some of our contributors are wrong? No, just that their experiences have created differences of opinion. As Shooting Illustrated’s Ammo editor, my opinions differ, as well. You’ll find either 135-grain Hornady Critical Duty or 124-grain Remington Black Belt +Ps in my 9 mms, and DoubleTap’s 160-grain TAC-XP Mann load in my .45s.

In that article, he asks nine associates from Shooting Illustrated what they carry for self defense ammunition. All of them have good resumes` and certainly know more about shooting than do I. Each of them carries a hollow point round of some variety. Mr. Mann mentions at the end of the article that he carries one of three different rounds. All of them use hollow point rounds. One of them is a round that I use on one of my 9mm guns for a number of reasons. Again, I won’t go into that here.

As do some of the other people cited in the July article, I try to match the round to the particular gun. Some guns “like” a particular ammunition more than others. It’s important to practice with any firearm you think you might use for self defense and find the ammunition that works best for you and the firearm.

I think any expert will tell you the same.

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After a long career as a field EMS provider, I'm now doing all that back office stuff I used to laugh at. Life is full of ironies, isn't it? I still live in the Northeast corner of the United States, although I hope to change that to another part of the country more in tune with my values and beliefs. I still write about EMS, but I'm adding more and more non EMS subject matter. Thanks for visiting.