Blunderbuss

A blunderbuss is a short range defensive weapon that reached its popularity in the 18th and 19th centuries. We will study this unique class of firearms in this post.

A typical blunderbuss is a muzzle-loader with a relatively short barrel that has a distinctive trumpet-shaped flare at the muzzle end of the barrel. The caliber of this weapon is typically large and it was often used by filling the barrel with multiple smaller pellets.

A Blunderbuss. Note the typical flared muzzle end of the firearm.

The original term for this weapon was donderbuss and this name appears to be Dutch. The word "donder" means "thunder" and "buss" means "pipe" in Dutch and German languages. Blunderbuss class weapons also appeared in handgun form, intended for cavalry. These early pistol blunderbusses often had decorations around the muzzle that looked like a dragon with an open mouth and hence were called "dragons". The cavalrymen who used such blunderbuss pistols were therefore called "dragoons". One such example of a dragon pistol is shown below:

The trumpet shape at the muzzle is the distinctive blunderbuss feature that distinguishes it from other firearms of that period. Since a blunderbuss is designed to fire several pellets at the same time, the flare was thought to increase the spread of pellets. The flare also makes it easier to load powder and pellets into the firearm. People mounted on horseback, or in a rocking coach or ship, found this feature very useful indeed. Also, since these are shorter weapons compared to the muskets of the era, they are more easy to manipulate on horseback or a ship deck. This is why they were very popular among cavalry, pirates, mail coach guards, naval personnel etc.

Blunderbusses designed for navies and pirates typically had their barrels made of brass instead of iron, to prevent rusting. Since they are designed to spread multiple pellets around, one such shot could easily deal with several closely packed enemies with a single shot. Hence, they were often carried into action by boarding personnel. 

While most blunderbusses were designed as everyday practical weapons, some blunderbusses were also works of art:

Blunderbuss commissioned by Tipu Sultan of  Mysore, India. Click image to enlarge.

Image licensed under the Creative Commons Attribution-Share Alike 3.0 Unported License by UploadAlt at wikipedia.com

The above weapon was custom made for Tipu Sultan, who ruled the Kingdom of Mysore in the 18th century. This fine weapon uses a flintlock firing mechanism and the barrel has engravings and gold inlays. Tipu Sultan was known to employ several European craftsmen and this weapon represents the latest in technology of that period.

As breech-loading weapons became more common in the 19th century, the blunderbuss gradually became obsolete and was replaced by the carbine.

What is a Bullpup Rifle?

In most rifle configurations, the trigger is located right underneath or very close to the the firing action. This means that the barrel starts right about where the trigger is. This has generally been the standard configuration for most firearms ever since firearms were invented. However, in the beginning of the 1900s, the concept of having a trigger ahead of the action was invented. This type of action is called a bullpup design and we will study about this type of design in this post.

Steyr AUG A1 rifle, one of the first successful bullpup designs.

Image licensed from Steyr Mannlicher GmbH & Co. under the Creative Commons Attribution 2.0 License/

Since the bullpup design has the trigger in front of the action, this means that the action sits close to the back of the buttstock and closer to the user's face. That means the overall length of the weapon is reduced. Also, since the stock contains part of the barrel and the action, the stock is much smaller and hence, a bit lighter than a conventional rifle. For example, the Steyr AUG rifle that you see in the image above has a 20 inch long barrel and uses 5.56 mm. NATO caliber cartridges, but is only 790 mm. long and about 3.6 kg in weight. By comparison, a conventional configured rifle, such as an M16A2, also has a 20 inch long barrel and uses 5.56 mm. NATO caliber, but is 1010 mm. long and 4 kg. in weight, which means that we save about 25% in length and about 10% in weight with a bullpup configuration.

The original bullpup design was invented in England in 1901. The Thorneycroft carbine was chambered for a .303 rifle cartridge and held five rounds in an internal magazine. It was 7.5 inches shorter and 10% lighter than the standard Lee Enfield rifle, which was the standard infantry arm of the British military and also fired a .303 cartridge. The Thorneycroft rifle suffered from recoil and ergonomics and was not adopted for military service. Later inventors tried to improve the design, such as a couple of French inventors in the 1920s and 1930s, but were not widely accepted. The Enfield factory came out with the EM-2 after World War II, but since it was not designed for NATO caliber, it faded from use very soon after. However, the British did not forget the concept of a bullpup configuration and later designed the L85 assault rifle in 1985, which is the current standard British military firearm.

Public domain image of a British L85A1 assault rifle

However, it wasn't the British that came out with the first successful bullpup configured rifle. That honor goes to the Steyr AUG which came out in 1977. The Steyr AUG was adopted by Austria initially and was later adopted by over 25 countries. Unlike previous attempts, the Steyr AUG was highly reliable, light and accurate and showed off the advantages of a bullpup configuration. France followed soon after with their new standard infantry rifle, the FAMAS, in 1978. This was followed by the UK's L85A1 and L85A2 models in the 1980s and early 1990s. Soon, many other countries followed suit, such as the Chinese QBZ 95, Singapore's SAR-21 and the Israeli Tavor TAR-21.

While bullpup designs are shorter and lighter (and therefore easier to maneuver in confined spaces), there are a few disadvantages as well. One of the early ones is that the ejection port of the rifle sits a lot closer to the user's face. Since most rifles eject spent cartridges to the right, left handed shooters have to shoot right-handed style to avoid getting a hot cartridge to the face. Some assault rifles (such as the Steyr AUG and FAMAS) get around this issue by allowing the user to easily swap the bolt and ejection cover around, so that left handed users can make the rifle eject to the left. Other rifles solve this by ejecting the spent cases forwards or downwards. Other issues with bullpup configurations are that the noise appears louder as the firing chamber is closer to the user's ears and magazine changes take a little longer, due to the ergonomics of this configuration. On the other hand, with the success of the Steyr AUG, many other militaries have also adopted rifles with bullpup configurations, because of the lighter and shorter nature of such designs.

Testing Firearms: Extreme Torture Test

In the last post, we studied some of the criteria that militaries follow when selecting a new firearm for their inventory. Among the extensive list of selection criteria is a set of torture tests, which test the firearm for reliability, functionality and ease of use under demanding conditions. While military tests are pretty demanding, they are not necessarily the toughest tests that a firearm may be subject to.

A few years ago, one enterprising gentleman decided to conduct a series of tests to determine exactly how reliable his Glock model 21 pistol was. He fully documented his process and even took video footage to prove that he'd actually conducted the tests.

The entire series test is documented here. The first couple of pictures in his original post seem to have disappeared, but a backup copy of that legendary post was also archived here, with the first few pictures intact. Note that the second link only has pictures, but not the links to the movies, which the first link contains. It is a very interesting read. The tests he conducted seem to be even more demanding than military tests. Bear in mind that this particular pistol was almost 10 years old already and had been well used and abused, before he even started conducting the tests. Also, half-way through the torture test process, he took the very same weapon to a weekend gun match!

While this is an extreme case of mistreatment, it is interesting to note that his weapon still managed to function after all that had been done to it. Note that the gentleman conducting the tests is a professional expert and such tests should NEVER be conducted by readers of this blog.

Testing Firearms: Military Acceptance Tests for Handguns

In the history of firearms, the most stringent requirements are usually applied when a weapon is selected for military use. This is because military weapons:

1. Should be able to work in demanding conditions (snow, heat, rain, dirt etc.)
2. Should be reliable, extremely resistant to damage and have long service life.
3. Should have good range and stopping power.
4. Should be simple to service in the field.
5. Should not be too expensive, because a large number of them will be ordered.
6. Should perhaps maintain compatibility with some other existing system (e.g. use cartridges of a specific caliber, be under a certain size to fit into vehicles, have at least a certain magazine capacity etc.)

The weapon that is selected by a military strikes a balance between these various factors. In this posting, we will look at some historical selection criteria for handguns from various regions around the world. 

The first set of criteria we will look at is the requirements of the US Army in 1906 for a new handgun. A few years earlier, US Army units in the Philippines had discovered that the standard Army revolver at that time, a revolver chambered in .38 Long Colt cartridge, was not sufficient to stop a charging Moro tribesman high on narcotics. With that in mind, the US Army Ordinance Department (headed by Colonel John Thompson, who later invented the Tommy gun), did some experiments and determined that a .45 caliber cartridge had the stopping power needed. Therefore, one of the first requirements of the new handgun was that it should be able to shoot the new .45 caliber cartridge. The US Army also subject all submitted handguns to the following torture tests:

• Each gun was to fire 6,000 rounds.
• Each gun would shoot 100 rounds at a time and then allowed to cool for 5 minutes before shooting again.
• Every 1,000 rounds fired, the gun was to be oiled and cleaned before firing again.
• After firing 6,000 rounds was completed, the gun was to be tested with deformed cartridges (i.e.) some that seated too deeply, some that were not seated enough etc. 
• The gun would be exposed to acid to test rust resistance, buried in sand and mud to test reliability etc.

Designs were submitted by Colt, Luger, Knoble, Bergmann, White-Merrill, Smith & Wesson and Savage. The Colt entry was designed by the renowned designer John Browning. The Browning design easily passed all the tests and became known as the M1911 pistol (as it was accepted officially in 1911). In the words of the selection committee:

"...the board was of the opinion that the Colt is superior, because it is more reliable, more enduring, more easily disassembled when there are broken parts to be replaced, and more accurate."

Now we will look at some of the requirements for the Austrian military in 1980, when selecting a new firearm. The Austrians were looking for a handgun to replace their old World War II era Walther P38s. Among the criteria specified:

• The design has to be self-loading (i.e.) it should load a new cartridge automatically after an old one is fired.
• The weapon must fire the NATO standard 9x19 mm. parabellum round (same as the old Walther P38)
• Magazine of the weapon should not require any means of assistance for loading.
• Minimum capacity of the magazine should be 8 rounds.
• All actions necessary to prepare the pistol for firing and any actions required after firing must be done single-handed, either right or left-handed.
• Pistol must be secure from shock. Tests to be conducted by dropping the pistol from a height of 2 meters onto a steel plate from various angles.
• Pistol should allow for disassembly and reassembly of the main parts, without using any tools.
• Maintenance and cleaning of the pistol should be done without tools.
• Pistol should not have more than 58 parts (which was the number of parts on the Walther P-38)
• Gauges, measuring and precise testing devices must not be necessary for long term maintenance.
• All components must be interchangeable with other pistols
• No more than 20 malfunctions are permitted during the first 10,000 rounds fired.
• After 15,000 rounds, each pistol will be inspected for wear and tear. The pistol will then fire an over-pressured test cartridge generating 5,000 bar (72,518 psi) which is almost 2x the pressure generated by the standard NATO 9x19 mm. parabellum cartridge (which only generates 2,520 bar (36,500 psi)). The critical components must still continue to function properly after firing this over-pressured cartridge.
• When handled properly, under no circumstance should the user be endangered by case ejection.
• The muzzle energy of the bullet should be at least 441.5 Joules when firing a 9mm. S-Round/P-08 Hirtenberger AG cartridge.

While there were submissions by many well known firearm manufacturers, it was the design by a then unknown firm called Glock that won this contest. Interestingly, since Glock had no previous firearm design experience, the Austrian authorities decided to subject it to the 10,000 round test with no more than 20 malfunctions. To everyone's surprise, the Glock design only suffered one malfunction in 10,000 rounds. None of the other manufacturers' submissions were subject to this grueling test because it was simply assumed that the others would pass as well!

Other torture tests included testing under extreme heat, ice, sand and mud and testing the firearms both after oiling and in an unlubricated state etc. They also considered other factors such as the time taken to train new shooters, number of parts to manipulate to make the weapon ready to shoot and ease of maintenance. Glock's design not only passed these tests with flying colors, they were far ahead of any other competing pistol, while also being 25% cheaper than the next lowest bidder. Glocks have since been accepted by many other militaries and police forces around the world.

Testing Firearms: Shotgun Pattern Test

People who use shotguns for hunting birds often use ammunition that contain multiple pellets or ball bearings. When such a cartridge is shot, the pellets spread out about a certain area, depending on the distance to the target. The pellets leave the shotgun in approximately the same order that they were in the cartridge and continue in a compact mass, until they hit a target, or fall on the ground. In order to reduce the area of concentration of the pellets, people employ various devices on the barrel such as a cylinder choke, skeet choke, modified choke, full choke etc. Of course, different choke types work differently with different ammunition types and hence testing is needed to determine the most effective combinations.

The standard way to test the shotgun pattern is to take a square sheet of paper around 40-45 inches long on each side. The tester mounts this sheet of paper at a distance of 40 yards. The tester then loads the shotgun with a cartridge that has a known number of pellets and shoots at the target. After this, the shooter looks at the paper and draws a circle of 30 inches diameter around the area with the greatest concentration of pellets.

Then the tester counts the number of holes inside this 30 inch circle. Say there are 150 holes inside the circle and the tester knows that the cartridge had 200 pellets loaded. Therefore the tester can say that this shotgun shoots with a 75% pattern for this choke and cartridge load combination.

The tester repeats this test five or more times with a given cartridge load and computes the average to get the shotgun pattern. Obviously, the type of choke used, the number and size of the pellets in the cartridge and the material of the pellets all may have an effect on the pattern density, so the tester tries the same test out with different combinations to find out which of these produce the best patterns.

In order to keep the tests accurate, one needs to make sure that the cartridges used in this test have the same number of pellets or ball bearings each time. One way to do this is to weigh the pellets before loading them into the cartridge. The following table illustrates the average number of pellets per ounce of different standard pellet sizes for both lead and steel pellets:

Of course, this assumes that the pellets are all of the same shot size. Some people don't believe in weighing the pellets to get a count. Instead, what they do is use a simple counting device, such as the one shown below:

Public domain image. Click on image to enlarge.

It consists of a flat trowel made of brass or steel, with a number of holes drilled into it. There is a sliding cover on the handle that can be used to vary the number of holes exposed on the face of the trowel. The tester pushes the trowel into a pile of pellets or bearings and slowly withdraws it. Pellets will stick to the holes and those that are not in any holes can easily be separated. Any misshapen or undersized pellets are also easily visible, so they can be removed as well. The tester can thus easily load the exact same number of pellets into multiple cartridges.

Testing Firearms: Machine Rests

When testing firearms and ammunition for accuracy and range, it is necessary to minimize human error as much as possible. When a human being shoots at a target, it is human nature that there is a lack of consistency between shots. A person may hold the firearm tighter or looser, shake the firearm more or less, vary the trigger pull force and react to the recoil differently from shot to shot. In order to eliminate variability for these factors, the industry developed machine rests (a.k.a bench rests). We will study these in this post.

A machine rest should ideally have the characteristic that it simulates a human shoulder or arm, so that it absorbs the recoil from a firearm as though a human were holding it. This is very important because if the machine rest is completely fixed, it will result in damage to the firearm's stock, bedding or recoil lugs. The machine rest should also be able to return back to zero (i.e.) back to its previous position before firing it. There should be some provision to pull the trigger by mechanical means, so that the trigger pull force and speed are consistent between shots. Some machine rests also have gauges to record the recoil force generated by the firearms as well.

In the above image, we have a machine rest designed in the 1890s, which was used by Field magazine to evaluate various firearms. It was made of iron, so that it was relatively portable. Points of interest are the spring balance H and toggle joint I. The spring balance records the recoil force and the toggle joint ensures that the varying strength of the spring at different positions is equalized out to provide a constant resistance. The device J, which is located under the stock of the rifle is an oil reservoir which has a cylinder and piston. This returns the firearm slowly back to its initial firing position, after it has been discharged.

Here's what a typical modern machine rest for rifles looks like:

This particular modern rifle rest is made by Hyskore and has interchangeable shock absorbers (compression dampers) for different rifle types. In this particular model, the shock absorbers are filled with nitrogen gas. It also has various knobs to adjust elevation and windage precisely and aim the rifle to the target. In addition, it has a remote controlled hydraulic trigger pull, so that there is consistency between one trigger pull and the next.

Next, we will look at another well known brand of machine rests used for handguns:

The above is a Ransom International made rest, which is pretty much the gold-standard when it comes to accuracy testing of handguns. Ransom International introduced the Master Series Rest into the market in 1969 and the Master Series models are still being sold today. In fact, most major handgun manufacturers use this model for accuracy testing. Like the other rests, this also simulates the grip and recoil absorption of a human hand very closely and it also has the facility to return the firearm back to its initial position after the shot. The trigger is activated by a little lever on the side, to provide consistent trigger pulls each time.

While major manufacturers use machine rests to ensure quality control of their products, these are also used by owners to evaluate their firearms and ammunition brands. For example, ammunition from different manufacturers come in different qualities. A tester can shoot X rounds each from different brands and determine which ammunition manufacturer produces cartridges that shoot uniformly best. Also, many new semi-automatic pistols have a tendency to shoot the first cartridge in the magazine in a different place than the other ones. Using a machine rest allows a tester to evaluate if a particular pistol has this characteristic. Some revolvers sometimes have some chambers in the cylinder that shoot at a different point than the rest of the chambers. Using a machine rest allows the tester to mark out which chamber(s) shoot differently and perhaps not load those chambers.

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.