Ammo Penetration Test

Here's a question for you:

What is your concern with "over penetration"?

The factory Tokarev rds are very fast, around 1500fps for the S&B that I chronographed. Couple that with the standard 85gr FMJ they come in and you get a round that is known for overpenetrating. One of the few factory pistol rds that will penetrate body armor.

That .357 had some radical impact!

kje54 said:

7.62x25 is a high velocity round designed to penetrate our military body armor, it will penetrate class II body armor and continue through the person wearing it. This means if you're using FMJ in that caliber for a self defense round you better be aware of anyone behind who you're shooting at as well as anyone behind that other person...........

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OK, I understand that.

Most people who post concerns with "over penetration" with respect to self defense fail to consider the fact that over penetration is a minor concern given the fact that the vast majority of rounds fired in self defense fail to hit their intended target in the first place. All those other "missed" rounds, which don't have the benefit of having lost any initial energy by virtue of passing through the body of the intended target in the first place.

Many also seem to forget that few, if any, self-defense rounds of any kind are NOT technically designed to penetrate so poorly as to not pass completely through a person's body in the first place.

One of the FBI standards on this is to consistently penetrate a MINIMUM of 12 inches and a MAXIMUM of 18 inches in ballistics gelatin.

A great many people have bodies for which ammunition designed to this specification WILL stand a very great chance of passing through their bodies.

All that said, it's definitely good to know the limitations and capabilities inherent with whatever one chooses to carry, as well as whatever one's personal limitations and capabilities are in handling it.

RetiredUSNChief said:

OK, I understand that.

Most people who post concerns with "over penetration" with respect to self defense fail to consider the fact that over penetration is a minor concern given the fact that the vast majority of rounds fired in self defense fail to hit their intended target in the first place. All those other "missed" rounds, which don't have the benefit of having lost any initial energy by virtue of passing through the body of the intended target in the first place.

Many also seem to forget that few, if any, self-defense rounds of any kind are NOT technically designed to penetrate so poorly as to not pass completely through a person's body in the first place.

One of the FBI standards on this is to consistently penetrate a MINIMUM of 12 inches and a MAXIMUM of 18 inches in ballistics gelatin.

A great many people have bodies for which ammunition designed to this specification WILL stand a very great chance of passing through their bodies.

All that said, it's definitely good to know the limitations and capabilities inherent with whatever one chooses to carry, as well as whatever one's personal limitations and capabilities are in handling it.

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You are exactly right about knowing its and your limitations and capabilities. I quite often cary my CZ52 when I am bushogging or doing other work out side. It is one of most accurate pistols I've ever had. I've hit Cotton mouths at 30 and 50 yds with it, free handed, from the seat of my Atv, one shot each. But I don't cary it in public as EDC for the exact reason the OP mentioned. My 9mm or .40sw is better suited for that, not to mention ammo and components are really scarce for 7.62x25.

kje54 said:

Saw this and it drew my attention because my primary full size carry is a Zastzva M57. I load mine with Hornady Critical Defense rounds to help prevent over penetration.

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Here’s a like for EDC with a Zastava M57!

Not many people doing that. I’m tempted to use the half cock and carry mine.

There is a noticeable difference between gel tests and real world shootings. Gel tests are important, and a great way to compare performance, but you need to always understand the penetration in gel and the penetration in a living body are not the same. Here is a great article that helps point that out.
https://www.activeresponsetraining.net/stop-worrying-about-overpenetration

RetiredUSNChief said:

OK, I understand that.

Most people who post concerns with "over penetration" with respect to self defense fail to consider the fact that over penetration is a minor concern given the fact that the vast majority of rounds fired in self defense fail to hit their intended target in the first place. All those other "missed" rounds, which don't have the benefit of having lost any initial energy by virtue of passing through the body of the intended target in the first place.

Many also seem to forget that few, if any, self-defense rounds of any kind are NOT technically designed to penetrate so poorly as to not pass completely through a person's body in the first place.

One of the FBI standards on this is to consistently penetrate a MINIMUM of 12 inches and a MAXIMUM of 18 inches in ballistics gelatin.

A great many people have bodies for which ammunition designed to this specification WILL stand a very great chance of passing through their bodies.

All that said, it's definitely good to know the limitations and capabilities inherent with whatever one chooses to carry, as well as whatever one's personal limitations and capabilities are in handling it.

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That's why it's important to never forget one of the basic covenants of gun safety!
"Be sure of your target and what's beyond it"

kje54 said:

I have a new SAR 9 that will probably become my full sized carry though it's almost twice as thick as the M57. The CZ52 was my first "modern" sidearm, loved that gun but ended up selling it many years ago, sometimes wish I hadn't.

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I have an M57 also, but I just like my CZ52 a little better,. Plus, I still use the leather holster it came with and I can't really damage the finish on the CZ easily, but my M57 still looks like brand new.

It's good to remember that the primary function of ballistics gel is to be a uniform--in the engineering sense of "repeatable--medium.
Gel only has a secondary use as a tissue simulant.
That's from the very non-uniform way mammals are made up of all sorts of "stuff" is rather random piles of squishy bits interspersed with hard bits.

That "engineering" need, to have a uniform testing medium, is also the "why" behind the FBI penetration requirements. It's not that they intend to through-and-through shoot people, but, that, in actual shootings, rounds which "worked" on people performed in gelatin to specification used.

Shooting at people seldom requires much more than 6 or 7 inches of penetration in human tissue. Conflating the results is easy enough to cause all this confusion, In ancient days of old, gunwriters relied on such repeatable media as "wet phonebooks" or "plumber's putty" or "pine boards" and so on. Later, the gallon jug of water became something of a fad. The Feebs, being the data-intensive lot they are just created a list of rounds that ended a situation satisfactorily. They then shot those into their chosen medium, and measured the result.

Much like a lot of the "conventional wisdom" on 7.62x25, which was just a revamped 7.62 mauser. Armor penetration was not a "thing" when the round was first fielded. It became a "thing" later in its service life. And was no considered important enough to prevent being replaced by 9x18mak.

The 7.62 Tokarev is really an amazing penetrator. When the surplus ammo was dirt cheap, I had the opportunity to fire it at all sorts of farm trash in my uncle's woods. It would penetrate interesting targets that one would normally only expect a rifle to pass through.

When I pulled RO duty for our local law enforcement when they used our gun club, I had the opportunity to fire it at a decommissioned class 3 vest and a polymer swat/riot helmet. Both were easily penetrated, leading to a cautionary lecture from the Detective to the officers in training that it isn't just rifles that are dangerous to body armor.

Other interesting things it will penetrate: 1960's all steel car door. 1950's steel refrigerator. Heavy, aprox 1/2" cast aluminum transmission housing. Steel truck and tractor rims. Aluminum 1/2 ton truck rim. Heavy plexiglass. Glass block window. Cinder block (one side with a single shot, pass through with multiple shots.)

The factory mil surp fmj is impressive as is. But you should see what they do when you insert a tungsten core. When I find the pics I'll post them, can't remember what folder on which computer I saved them.

True AP ammo is crazy. Clean quartering shots on a buick. Never fired AP in a handgun but I have fired 308 and it was so impressive. Steel is like plastic.

There is a noticeable difference between gel tests and real world shootings. Gel tests are important, and a great way to compare performance, but you need to always understand the penetration in gel and the penetration in a living body are not the same. Here is a great article that helps point that out.
https://www.activeresponsetraining.net/stop-worrying-about-overpenetration

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https://www.activeresponsetraining.net/stop-worrying-about-overpenetration

Unfortunately the article is chock full of misinformation. For example:

Almost all of the rounds we tested penetrated a full 16″ of gelatin. Folks were asking me why a bullet would need to penetrate 16″ when the heart and other vital organs are only a few inches deep in the chest cavity.

The reason is that penetration in gelatin is not the same as penetration in human flesh and bone.

The human body is not a consistent medium. Muscle, fat, organ, and bone all have different mass, density, hardness, and flexibility. In general, a bullet will penetrate much deeper in gelatin that it will in human flesh.

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Studies have shown that the the range of penetration in a human body, in any given shooting, can indeed be greater than the penetration in properly prepared and calibrated Type 250A ordnance gelatin, however the AVERAGE penetration depths are the same.

In addition soft tissue densities do not substantially affect penetration depth because at handgun bullet velocities the primary resistance to bullet penetration is inertial force as opposed to shear force.

Ordnance gelatin is currently the only realistic soft tissue simulant for terminal ballistics testing. Results in ordnance gelatin have been compared to thousands of actual shooting to verify and validate it's equivalence to living human soft tissues.

When bone is encountered a bullet's terminal performance cannot be accurately predicted due to several variables. Performance in bone is what it is. The only performance we want when bone is encountered is for the bullet to blast through to reach and destroy vital tissues, which are all soft tissues. To see how well bullets perform when bone is encountered, the FBI's windshield test provides a good indication. The RCMP performed a series of tests with rib bones and found them to have a negligible affect on a bullet's terminal performance.

When terminal performance in human tissues radically departs from terminal performance observed in properly prepared and calibrated Type 250A ordnance gelatin there's a good reason for it, one just has to look deeper to determine why. When the circumstances of these kinds of shootings are replicated using ordnance gelatin the results have been found to match.

The primary reason for the diminished penetration in an actual body is the presence of skin and bone.

Skin is very elastic. A bullet uses up a lot of energy stretching the skin before the skin actually breaks. Most ballistic experts believe that the skin itself is equal to one to two inches of gelatin penetration.

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The resistance of skin to bullet penetration only matters when the bullet tries to exit the body. The bullet must stretch unshored skin enough to cause it to tear to allow the bullet to exit. Whereas an entrance wound on skin simply crushes skin tissue - there is no additional resistance caused by the skin stretching because the underlying body shores the skin.

We want a bullet that penetrates 12″-18″ of gelatin. That translates to roughly 6″-10″ of human flesh, depending on the structures hit.

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This is false information that is easily disproved by studies comparing thousands of actual shootings to results observed in properly prepared and calibrated Type 250A ordnance gelatin.

It's good to remember that the primary function of ballistics gel is to be a uniform--in the engineering sense of "repeatable--medium.
Gel only has a secondary use as a tissue simulant.

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Properly prepared and calibrated Type 250A ordnance gelatin is a verified and validated realistic soft tissue simulant. It accurately records the permanent cavity, temporary cavity, fragmentation and yaw of bullets in soft tissues.