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 - II

In our last post, we looked at some tests done against many early firearms, mostly arquebuses and muskets. While we studied some of the tests, it might be a good idea to actually present some of those results in a bit more detail, so we can understand it better.

Examples of arquebuses. Click on the image to enlarge. Public domain image.

As was mentioned in the previous post, during 1988 to 1989, staff members of Steiermärkisches Landeszeughaus (Steyr Provincial Armory)  in Graz, Austria, conducted tests using 16 firearms dating from 1571 to post-1750, with equal numbers of specimens from the 16th, 17th and 18th centuries. The guns were mostly mass-produced specimens, such as might be typically issued to infantry troops. Three of the weapons had rifling, the others were smoothbore guns. A couple of the guns were rejected after early inspection revealed that they had potentially dangerous weaknesses in the metal. The remaining 14 weapons were test fired 325 times under controlled conditions, in a testing range operated by the Austrian Army. As part of the tests, they also brought two modern production assault rifles and a modern pistol used by the Austrian military, so that they could compare the results against modern firearms.

The following charts below summarize the various firearm dimensions and the results of velocity measurements:

Physical Characteristics of the various firearms. Click on the image to enlarge.

Velocity measurements of the various firearms. Click on the image to enlarge.

A few notes on the results presented above:

1. The modern weapons are highlighted in yellow background at the bottom of the images. 
2. The "Spanish" weapons are actually made in Austria, but the Spaniards were the first to equip their troops with heavy muskets in the 1520s, which is why heavy muskets of that era are generally called "Spanish muskets", irrespective of where they were actually made.
3. The results presented above are in metric units, in keeping with the spirit of the original tests. To convert mm. to inches, divide the numbers by 25.4, to convert weights from kg. to pounds, multiply the numbers by 2.2, to convert grams to pounds, multiply the numbers by 0.0022, to convert grams to grains, multiply the numbers by 15.43 and to convert velocity from meters/sec to feet/sec, multiply the numbers by 3.3
4. Caliber is actually the nominal caliber of the bullet (i.e the bore diameter). We read something about this when we discussed 5.56 mm. vs. .223 ammunition earlier.
5. Pistol weapons were shot at targets at 30 meters (100 feet) ranges, whereas rifles were shot at targets at 100 meter (330 feet) distances. This is why rifle velocities are measured at both 30 and 100 meters.

The first thing we note is that all the older weapons have much larger dimensions than modern weapons. In fact, the only two older weapons that are smaller in length are the two pistols, which are shorter than modern rifles, but not by too much. The modern pistol is much smaller in size than everything else. Similarly, older weapons are generally much heavier than modern weapons, especially the ones from the 16th and 17th centuries. Advances in metallurgy have made it possible for modern firearms to be both stronger and lighter than the ancient firearms. The calibers of weapons have also significantly reduced in modern times. Powder weights are somewhat harder to compare, because the older weapons use black powder, whereas modern weapons use smokeless powders, which are much more efficient in propelling bullets. However, they are still listed above, so that the reader can see how much less weight of powder modern weapons use.

Now on to the muzzle velocities, which are shown in the second chart above. The interesting thing is that the slowest muzzle velocity measured is actually from a modern weapon (the Glock 17 pistol). Of course, it should be noted that this Glock pistol was the shortest weapon in the test with the smallest barrel. It also uses a lot less powder (0.4 gm.) versus the other firearms (albeit, smokeless powder, which produces more thrust). The ancient firearms are all generally between 450 and 550 meters/sec., with the exception of the two ancient pistols, which clock in at 385 and 392 meters/sec. The two modern rifles shoot much faster than the others, exhibiting nearly double the muzzle velocity compared to the ancient firearms. It must be noted that all the weapons are firing at supersonic velocities initially, even the ancient weapons using black powder (speed of sound at sea level is about 330 meters/sec. (or 1125 feet/sec.))

Also, note the change in velocities when measured at 30 meter and 100 meter ranges. As we studied in the previous post, round balls lose velocity at almost 3 times the rate that conical bullets do. The modern weapons all fire conical bullets, whereas the ancient weapons all fire round ammunition balls and we can see the results clearly. For instance, at 30 meter range, the FAL rifle only loses 20 meters/sec velocity (835 vs 815 meters/sec.), whereas the ancient weapons lose velocity a lot quicker. In fact, at 30 meter range, some of the bullets from ancient weapons are slower than that fired from the Glock 17, which had the slowest muzzle velocity initially. At 100 meter range, the velocities of older weapons are significantly less, with many of them travelling at under 300 meters/sec. (about 1000 feet/sec.) This means they also lose penetrative power much more rapidly than modern weapons do. This is the reason why most ancient commanders told their men to not shoot until about 60-70 meter ranges or even closer than that.

The interesting thing is that the two older pistols, while they shot at lower velocities than the muskets, they still retained a good bit of their velocity at 30 meters range, which means that they could inflict a fair amount of damage at shorter ranges. This explains the popularity of pistoleers on horseback, such as the German Reiters of the 16th century. These troops could quickly ride close to the enemy, discharge their pistols and then ride back. Some military writers of that era noted that a squadron of Reiters could easily beat a comparable squadron of traditional cavalry

In our next post, we will look at the same weapons and compare their respective penetrative powers and shot dispersion.