Effectiveness of Old Firearms - IV

In our last post, we looked at a series of penetration tests done in Graz, Austria, to weapons from the 16th, 17th and 18th centuries, compared to modern weapons. But what about accuracy, the reader asks? Today, we will study the accuracy of those ancient weapons against modern weapons.

As was mentioned in the earlier posts in this series, the firearms were typical mass-produced weapons used by infantrymen in the past. The testers also picked two modern rifles and a modern pistol to test against. For testing the accuracy, the firearms were all mounted on a frame and sighted to a paper target at 100 meters (330 feet) distance for rifles, and 30 meters (100 feet) distance for pistols. The paper target measured 167 x 30 cm. (or 5.5 x 1.0 feet), simulating the frontal area of a standing enemy, with an even larger secondary paper target behind it, to track where the bullets were hitting (even if they hit outside the primary target). The actual number of shots fired per weapon varied, but there were about 18 shots fired from each. The table below presents the results:

Results of accuracy tests. Click on the image to enlarge.

As before, a few notes on the results:

1. The modern weapons are highlighted with yellow background at the bottom of the image.
2. The height and width refer to the dimensions of the smallest rectangle that could be drawn around all the bullet holes. The next column is the area of the this rectangle. The last column is the probability that the primary target was hit at all.
3. In keeping with the spirit of the original tests, results are in metric units. To convert cm. to inches, multiply the numbers by 0.3937. To convert the area from sq. cm to sq. inches, multiply the numbers by 0.155.
4. To eliminate human inaccuracy, all weapons were fired from a frame and triggered electronically, bypassing their normal firing mechanisms.
5. Muskets and rifles were tested on targets at 100 meter (330 feet) distance, whereas pistols were tested on targets at 30 meter (100 feet) distance.
6. The flintlock barrel that was used as a pressure tester, was not fired at targets for these tests, therefore it shows up in the chart with green background and the words "no applicable data".
7. The wheellock musket made in Southern Germany in the first half of the 17th century shot so inaccurately, that the tests for it were cancelled. This is shown in the chart with pink background and the words "Tests cancelled due to excessive scatter".
8. The three best performing ancient weapons are highlighted in gray background.

As can be seen from the above figures, long-barreled weapons performed very poorly in the accuracy tests. Only one musket (The 9th weapon - flintlock musket from Austria, made in the second half of the 18th century) showed any good probability of hitting the target (83%). Not surprisingly, this happened to be a rifled barrel. However, two other rifled weapons (the 1st one and the 6th one) performed really badly. In fact, the 6th weapon (the wheellock musket, South German, from the first half of the 17th century) scattered its shots so badly that the test was cancelled for it. For 4 out of the 13 guns tested, the enclosing rectangle's area was larger than the area of the primary target, and for 2 others, it was nearly the area of the primary target. This means that a total of 6 of the 13 long guns shot so inaccurately at 100 meter distances, that they only hit their targets by pure random luck! This is why battlefield commanders of the 16th-18th centuries ordered their troops to shoot at smaller distances, such as 50-70 meters (160 to 230 feet) or even closer than that, in order to be effective. One of the primary reasons for inaccuracy of the ancient firearms is the shape of the bullet, which is a round ball. At distances of 100 meters, the Magnus effect, which we studied earlier, plays a significant role in the ball deviating away from the target. By contrast, modern bullets are tapered and are more stable when flying in the air.

On the other hand, the two ancient pistols fared much better at 30 meter ranges. While they had much larger enclosing areas than the modern pistol, they did manage to put most of their shots into the human-sized target. In fact, one of the two ancient pistols had a 99% probability of hitting its target. Therefore, at closer distances that pistols were used at, they could be pretty deadly. At closer distances, the deviation caused by the Magnus effect is not large enough to cause the ball to miss its target. This explains the number of injuries and deaths in pistol duels, as well as the effectiveness of pistol cavalry units, such as the German Reiters troops.

Effectiveness of Old Firearms - III

In our last post, we looked at a study done in Graz, Austria, that compared mass-produced soldier weapons from the 16th, 17th and 18th centuries against modern weapons used by soldiers today. In the last post, we studied the velocities of the various firearms. Today, we will study how the various weapons fared in penetration and accuracy tests.

For the penetration tests, the testers used different types of targets: gel blocks, wooden boards, modern steel plates and 16th century armor plates. Gel blocks are one of the modern ways to evaluate penetration, since it approximates muscle tissue. If the gel blocks are prepared carefully, they can be produced repeatedly with the same consistency, thereby providing for more reliable comparative tests with multiple firearms.

Results of Penetration Tests. Click on the image to enlarge.

As before, a few notes on the results:

1. The modern weapons are highlighted with yellow background at the bottom of the image.
2. The flintlock barrel that was used as a pressure tester, was not fired at targets for this series of tests, therefore it shows up in the chart with green background and the words "no applicable data".
3. The targets were placed at distances of 30 meters (100 feet) and 100 meters (330 feet) and the penetration was measured in millimeters (mm.). In keeping with the spirit of the original tests, your humble editor has not converted these into imperial measurements, but can be easily done as follows: To convert meters into feet, multiply the numbers by 3.3. To convert mm. into inches, multiply the numbers by 0.039. To convert cm. to inches, multiply the numbers by 0.39
4. The targets were made of steel and wood. For the wooden targets, they were made using wood from spruce trees.
5. The theoretical maximum range of the weapons was determined by firing each weapon at 60 degree angle. 

As the chart shows, the pistols, whether modern or ancient, all have similar penetrative properties at 30 meter range. Although the modern Glock had the best penetration on both steel and wooden targets, it didn't outperform the ancient pistols by that much in the penetration tests. On the other hand, it has a much longer range than the other pistols (and even the ancient muskets). This is because the tapering bullet does not lose velocity as quickly as a spherical ball does. 

On the other hand, the modern rifles simply outperformed the ancient muskets by a large margin in the penetrative tests, as well as the maximum range test. The AUG firing the NATO 5.56x45 cartridge penetrated about 2x to 3x the depth of the ancient muskets and the FAL firing the NATO 7.62x51 cartridge penetrated about 3x to 5x the depth of the ancient muskets. The maximum range of the modern rifles also far outperformed the ancient muskets.

However, there are other interesting results that became apparent by this series of tests.

Since the ancient weapons all fire larger spherical balls, (the calibers are listed in our previous post) they left larger volumes of wound cavities at shorter ranges. This is because, at close distances, the spherical balls were moving fast enough to do some serious damage. For instance, the flintlock musket that was made in Suhl in 1686, fires a 17.8 mm. diameter ball weighing 30.93 grams and at 9 meter distance (about 30 feet), it left a cavity of 530 cm³. Similarly, the flintlock musket from Austria that was made in the second half of the 18th century, fires a 16.4 mm. diameter ball weighing 26.73 grams and left a cavity of approximately 369 cm³ at a distance of 9 meters.

By contrast, modern weapons fire much smaller tapered bullets, which generally do less damage. At the same 9 meter distance, a modern Steyr AUG rifle firing a 5.56x45 mm. cartridge only left a cavity of 101 cm³.

On the other hand, as the distance increased, the tests showed that the wound cavity made by spherical balls decreased much more significantly. The same musket that made a 369 cm³ cavity at a distance of 9 meters, made a 155 cm³ cavity at 100 meters distance. In contrast to this, the Steyr AUG rifle which made a a cavity of 101 cm³ at 9 meters range, left a cavity of 70 cm³ at 100 meter range. This means that the modern rifle only lost approximately 30% of its penetrative powers at this distance, whereas the older weapon lost about 60%. Still, the older weapon left a much larger cavity, even at 100 meters distance. This explains the extremely horrific wounds experienced by soldiers in the 16th to 18th centuries.

Additionally, the tests showed that the shapes of the wound cavities are also different. Spherical musket balls leave trumpet-shaped wounds. They are widest at the point of entry and taper steadily down in diameter as the ball slows down and loses energy. By contrast, modern bullets leave cavities of a completely different shape:

Cavity left by a 5.56 mm. bullet.

The above image shows the cavity left by a NATO 5.56 mm. bullet in ballistics gel. As you can see, the bullet first creates a smaller hole in the beginning as it enters the target, but as it moves deeper into the target, it starts to tumble and fragment and leaves a much wider hole than the bullet diameter as it moves further in.

The tests also measured the protection offered by body armor. Modern mild steel plate of 3 mm. thickness of the same steel grade as those used for the penetration tests tabulated above, was lined with two layers of linen and then placed before a gel block. The entire target was mounted at a distance of 9 meters. The flintlock musket from Austria that was made in the second half of the 18th century, was fired again. Remember that this same musket had left a 369 cm³ cavity at an unprotected target at the same distance earlier. When fired at the protected target, the bullet did manage to penetrate through the metal and linen and entered the ballistics gel. However, it only penetrated for a short distance and left a cavity of 25 cm³. The bullet and the armor plate both splintered and some of these splinters penetrated into the gel block up to a depth of 80 mm. (or about 3.15 inches).

Incidentally, the testers also fired the flintlock pistol made in Ferlach in the 1700s, into a gel target with no protection at the same 9 meter distance and it left a cavity of about 23 cm³. This shows that the 18th century flintlock pistol fired at an unprotected target produced a wound pretty similar to the wound produced by the 18th century musket fired at a protected target.

The most interesting result of the Austrian tests involved a pistol shot at a breastplate made in the 16th century, at a distance of 8.5 meters. The breastplate was part of an armor set made to protect horses. It was manufactured in Augsburg sometime between 1570 and 1580 and made of mild steel, which was cold-worked. The thickness of the plate was approximately 2.8 to 3.0 mm throughout and had a Brinell Hardness Number of 290. The plate was mounted on a sandbag, covered with two layers of linen cloth, to simulate what a typical knight on the battlefield would wear. The pistol used for this test was the wheellock pistol made in Nuremberg ca 1620, firing a 12.3 mm. ball weighing 9.56 grams. At the point of impact, the ball was measured traveling at around 436 meters/second. The ball completely penetrated the breast plate, but it lost all its kinetic energy in doing so. The ball became heavily deformed, lost about 24% of its mass and got stuck in the linen cloth. No part of the ball managed to penetrate to the sandbag and there were no secondary splinters from the armor to cause any damage either. This means that our 16th century knight would have probably survived a pistol shot at close range with nothing more than a few bruises on his chest. This shows that the 16th century armorers actually had some pretty good skills and understood cold-working techniques well to provide such hard armor.

In our final installment of this series, we will study the accuracy results of the same weapons.

What's the deal with teflon coated bullets?

During the early 1980s, there was quite a bit of controversy about teflon-coated bullets. Some news articles even went so far as to label them as "cop killers". The reader is probably thinking at this point, "Teflon? Isn't that the stuff that they coat non-stick cooking pans with? Why is that so dangerous?" This article aims to clear up the mystery.

Teflon coated bullet

Our story starts in the 1960s, when a company called KTW Inc. (named after the founders last names, Kopsch, Turcos and Ward) from Ohio was trying to develop a bullet with better penetration characteristics. Common handgun bullets which were largely made of lead, had the problem of deforming upon hitting a hard surface, such as a car door or a windshield, and became less effective after they deformed. KTW was trying to invent a better bullet for use by police departments (in fact, one of the founders, Daniel Turcos, was a police sergeant at that time and the other two founders worked in the coroner's office of the Ohio police department).

They eventually settled on a bullet design that consisted of a steel core, with an outer jacket made of hardened brass. This bullet offered much better penetration than older lead bullets, but it had a problem because of the hardened brass layer on the outside of the bullet. This hard layer did not engage the handgun's rifling very well and the friction caused the barrels to wear out prematurely. To reduce the barrel wear, the inventors coated the outside of the bullets with teflon, because teflon is very slippery and is one of the best lubricating substances known to man (the same reasons why teflon is used to coat the surfaces of non-stick pots and pans).

In 1982, NBC ran a special television report on these bullets where they argued that these bullets were a danger to police officers (many police departments had requested NBC not to run that program). After that television show, many American gun-control groups started to call these bullets as "cop killers" because they could penetrate the ballistic vests that many policemen used to wear at that time. Unfortunately, many of these reports wrongly reported that the teflon coating was the reason that these bullets had better penetration, rather than the hardened brass jacket which was the real reason. Movies and TV shows continued to spread the myth that coating ordinary bullets with teflon suddenly made them capable of piercing armor plates.

Because of the publicity, North Carolina, South Carolina, Oregon and Oklahoma have laws that make it illegal to possess teflon coated bullets, while Virginia makes it illegal to use teflon coated bullets to commit a crime.

KTW stopped producing these bullets in the 1990s and they're not encountered as much these days. However, there are other manufacturers who coat their bullets with other lubricating substances, such as molybdenum disulfide, wax, lubalox etc.

Testing Firearms: Bullet Penetration

One of the tests of cartridges is the penetration test. This test shows how effectively a particular type of bullet will penetrate its target. As we studied earlier, there are different types of bullets: hollow point, full-metal jacket, soft-point etc. There are also different types of targets: For example, a bullet shot at vermin such as rats, needs to expand really quickly after it hits the target, to have any effect on the animal. It should not exit out the other end without expanding first. However, the same bullet will not be as effective on a larger animal, if it expands too early, as it will not hit a vital organ and not ensure a quick kill.

Penetration testing in earlier years used to involve using thick brown paper sheets or strawboards. These were stacked together horizontally and shot at, and the count of the number of sheets or boards penetrated were tallied up and compared to each other. The following image shows one of these test racks

Public domain image. Click image to enlarge.

In modern times, the medium of choice is a material called ballistic gelatin. The reason for using ballistic gelatin is because it has about the same density of human or animal tissues. Ballistic gelatin is also preferable to actual muscle tissues, since its properties can be more carefully controlled to produce a consistent medium for doing multiple comparative tests. It must be noted that ballistic gel doesn't completely simulate actual body structure, since it doesn't have any skin or bones, which are much tougher and harder than flesh tissue.

The standard formula used for testing is called "10% ballistic gel". It consists of mixing 1 part by mass of powdered ballistic gel formula with 9 parts of water at a temperature of 54.5 C (130 F). The mixture is poured into standard molds (per the INS National Firearms Unit test, the standard mold size is 6" x 6" x 16" for handguns. Other standards bureaus may have different standard test sizes) and the mixture is chilled to 4 C (39 F) and allowed to set.

Before conducting the actual tests, the gel block is initially calibrated by firing a standard 4.5 mm. steel ball bearing from an air gun, over a chronograph and into the gel block. The air gun should shoot the ball bearing at a velocity of 183 ± 3 meters/sec. (600 ± 10 feet/sec.), which can be verified by the chronograph. If the gel block was prepared correctly, the penetration of the ball bearing should be between 8.3 to 9.5 cm. (3.25 - 3.75 inches). If this is the case, then the gel block may be used for standardized testing.

In most police agencies, testing teams usually test for penetration in other materials as well: gelatin, heavy clothing, steel, particle board, plywood, automobile glass etc.

For homebrew testers who don't have access to ballistic gel, people generally use wet newspaper blocks or wet phone books or a line of 1-gallon jugs filled with water.