Ammo Testing is Complicated

Expanded Hornady Flex Lock bullet

Cartridge testing is complicated by any standard. Research and development must end at the ballistic lab with bullets being fired into gelatin when personal defense and service use is the goal.

Hornady .45 220-grain Flex Lock bullet after meeting glass.
A Hornady .45 220-grain Flex Lock bullet after meeting glass. Glass is hard on projectiles.

The combination of science is demanding. First, a load is developed that operates at a safe pressure for the given cartridge while providing maximum performance. This means careful powder and primer selection. A full powder burn and good accuracy are desirable.

Next, we test wound ballistics. Over the previous century, tests have been conducted using dry cadavers, pine boards, European glue, wax, water, wet newspaper, and most famously and recently ballistic gelatin. Gelatin is the closet media we have to flesh and blood and human and animal tissue, yet it really isn’t close at all.

Sale ends July 21, 2019

Sale ends July 21, 2019

Gelatin is useful for comparing one load to the other but not necessarily for comparing how the loads will actually perform in a living target. The results are close enough for government work, and the ammunition companies, military groups and police agencies and institutions use gelatin for ammunition testing. Gelatin alone of the viable test media gives a permanent representation of the wound channel. As an example, I often use water for comparing one load to the other. It is repeatable, as well as reliable, and water results are consistent. On the downside, there is no record of the effect, and of course, water isn’t as scientific as gelatin. However, water is much more practical for most of us.

Speer Gold Dot bullet in gelatin with green dye
This is a Speer Gold Dot bullet in gelatin.

There are many factors to consider when choosing ammunition. Recoil, control in the individual handgun, a clean powder burn, good bullet pull, limited muzzle blast and flash, and reasonable accuracy are important. A loading with a balance of expansion and penetration is desirable for personal defense use.

Preparing gelatin for testing is a demanding procedure. The gelatin must be properly mixed, and it is tested for consistency, so the results will be valid and repeatable. It is expensive to scrap a 40-pound block of gelatin that isn’t mixed properly. Consistency is vital.

Agencies across the world must be able to compare ballistics results obtained in the United States. The term repeatable and verifiable are heard often. Studies of so-called street results have little value compared to lab testing, although these results are worth study and may be interesting. Some so-called studies claim to have confidential reports and secret sources. Their validity is zero. Science doesn’t ask you to believe, science presents the facts. As an example, a few years ago some writers actually convinced a gullible minority that secret testing—involving shooting alpine goats—had been conducted! The technical is seldom as exciting as fiction, but it is reliable.

Expanded Hornady Flex Lock bullet
An expanded Hornady Flex Lock

As I have stated, the results obtained in scientific testing are useful in comparing one load to the other. I do not wish to discourage anyone from mixing their own gelatin as there are many careful people capable of doing this work; it is simply a chore that most would not care to perform. There is a considerable investment in time and material. You have to know how to read a wound cavity for the results to be worthwhile.

In water testing, penetration and expansion are tested. The bullet is found in the skin of a water jug, in the jug, or between jugs. The bullet is captured by the gelatin block. The wound cavity is represented in the block. Most jacketed hollow point bullets expand in an 18-inch block and stop. The gelatin block expands a bit and often snaps back to shape. You look over the entire cavity and determine the results.

You will observe how quickly the bullet expanded past the initial caliber-size hole. Some bullets will penetrate the same length but begin expanding at different points. How deep and wide is the cavity, that is the question. This makes for a measureable complete wound volume.

Hornady 220-grain FlexLock .45 ACP bullet in ballistic gelatin
The Hornady 220-grain FlexLock .45 ACP bullet.

Two wound cavities with the same depth of penetration may have different characteristics. The FBI measures the total wound volume. The FBI also demands a minimum of 12 inches of penetration with 18 inches being desirable. This is reasonable considering the fact that the felons arms may be extended as he is firing at you—demanding penetration through the arm bones.

Heavy clothing or light cover may be part of the problem. Or, you may be dealing with a heavy and thickly muscled individual. Another consideration is the length of the beginning of the wound channel, sometimes referred to as the neck. If the neck is relatively short, then the bullet has begun expanding early. If the neck is long, expansion began later. This isn’t a trait that may be measured with other media.

Hornady .45 220-grain Flex Lock bullet after meeting glass.
A Hornady .45 220-grain Flex Lock bullet after meeting glass. Glass is hard on projectiles.

A rapidly expanding bullet may be desirable in home defense. An average-sized individual with light clothing will be addressed well by such a loading. On the other hand, the larger the opponent and the more heavily clad—as in a winter scenario—the bullet that begins expansion later might be the better choice. The choice, which depends upon an individual scenario, is common wisdom. However, some cannot afford the luxury of the individual scenario, and wisely plan for the worst-case scenario. In this case penetration is favored.

The final arbiter of effectiveness is shot placement. A shot to the arterial region that produces blood loss through damage is most desirable. The lungs are not particularly difficult to penetrate. The body has both hollow and solid organs. A hit to one of the solid organs often produces more shock and more bullet expansion.

Bullets that expand well are often stopped by the heavy skin of the back. This layer or hide is more resistant to damage than commonly realized. Flesh, blood, bones, and solid organs are a mix in the body that cannot be easily duplicated.

Bob Campbell firing a 1911 .45 ACP pistol
Firing for reliability is part of the test program. Muzzle flash and a full powder burn are measured.

The bullet may not expand at all. If the bullet nose strikes bone and the nose closes, then there will be no expansion. (A situation the Hornady Critical Defense bullet was designed to defeat.) Gelatin is useful for testing because it homogenous. This simply means it is the same in detail through the gelatin block and does not differ. There have been attempts to modify gelatin for greater realism, such as the Royal Canadian Mounted Police testing of gelatin with bones interspersed in the mix. While interesting, such experiments simply give a rough idea of bullet performance in human beings, although the testing is valuable and valid.

The RCMP also tested handgun ammunition at 50 yards, reasonable in light of the ranges of climate and the real estate patrolled by the RCMP. A few individuals with little qualification to comment have argued against the FBI’s minimum penetration standard. This isn’t wise. The FBI has more resources than any gun writer and most ammunition factories. There is good reason I cannot recommend small calibers. The baseline of .38 Special +P and 9mm Luger +P is a good one. These loads offer a high degree of protection for those that practice. And, in the end, that is what matters—practice, shot placement, and marksmanship.

Which self-defense ammunition do you prefer? Why? Share your answers in the comment section.


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Comments (36)

  1. When you can’t argue the merits because you’re wrong, apparently your next logical step is name calling and berating. But that’s OK, what’s important is the right information gets out to the many people that likely read these.

  2. So are you saying you don’t like me?

    Honestly, I don’t care, what I care about is the right advice is given to the large number of people who likely read this.

  3. What part of handling 100+ reports of non-police involved shootings don’t you understand? Those are reports where people state what happened in shootings they were the victim (sometimes turned out suspect) in, describing the way it happened so that I can make a report on the incident. This is real life experience of hearing the mechanics of the incident, my personal “data.” Again, I don’t think there is an actual database of whether the millions of shootings that take place across the country involved moving or static “targets,” but I see no reason why Cleveland should be any different than any other city. How many of your co-workers have been in shootings that can describe what happened? I had dozens. But then again, LE shooting are so dramatically different from civilian shootings (sarcasm intended). None of what I posted is in any way trying to make myself sound like something other than what any other big city cop might go through over the course of their career, it IS qualifying me to say what I said, what have YOU done for your community or country over the course of your life? Clearly you have an anti-cop bias by bringing up the fact that officers occasionally lose a fight on the street, OF COURSE it happens, we’re just human beings like anyone else, except we have to carry around about 15 pounds of equipment and body armor. Some of that will help you, some of that will hinder you, especially if you had to chase someone prior to fighting with them. But those are pesky little details a person like you couldn’t care less about. So if a database is what you’re looking for, one doesn’t exist, but if life experience/training and common sense don’t work for you, and you don’t think using the BEST ammo you can get your hands on is important, then go ahead and carry crappy ammo and make sure you take very careful aim before you shoot if you’re ever in a deadly force situation.

  4. I carry a .40 and alternately load with rapid expansion and delayed expansion ammo. I was trained to “double tap”, so there is going to be one each sent to greet the recipient.

  5. Most gunfights take place at 21 feet or less. I carry a Walther PPQ 9mm. I use RIP Ammo for two reasons. I don’t want the bullet to pass through an assailaint and strike an innocent bystander is reason number one. The second reason is when RIP strikes it breaks into 7-9 pieces each traveling a different direction making it more likely one will strike a vital organ. Destructive ability is top shelf. Remember, the one who walks away from a gunfight is the winner.

  6. Don,t over analize, it is not complicated. I have used wet telephone books for years. You can get an idea of the wound channel and penetration. The results are repeatable enough. Just shoot a lot of different bullets and loads, and compare one against the other.
    For a self defense gun most hand guns are poor threat stoppers. Don,t think so? Try hand gun hunting. The difference between a deer shot with a 308 Win and a 357 Mag is like night and day. The deer I have killed with a 357 all hopped off and died, most looked like they had not been hit. The last 5 deer I shot with a 308 did not take another step.
    Most Hand gun loads do not penetrate well and cannot be relied on to expand.
    Since you cannot stuff a 308W or 12 Ga.down your pants you are kind of limited to a hand gun for a carry gun.
    Pick the one you want. Pick a load that penetrates and creates a reasonable wound channel. Practice and pray you never have to use it.

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