Biathlon

A long while ago, we had studied a shooting sport called "silhouette shooting". A couple of years ago, we studied "clay pigeons", just before the London Olympics. As a theme, we will study sports where shooting plays a part, in the next few posts. Today,we will study the Biathlon, a sport that is played in cold weather and is part of the Winter Olympics.

The sport of biathlon is a mixture of cross-country skiing and rifle shooting. It has its origins in military exercises in Scandinavian countries, in the 18th and 19th centuries. Each competitor has to ski through a cross-country course, while carrying a rifle and a small amount of ammunition. At different stages of the course, the competitor has to stop at a shooting range and shoot five shots at targets, at a range of 50 meters (160 feet). There may be two or four shooting ranges throughout the course and half of these are shot at in the prone position and the other half in the standing position. The size of the targets depends on the position used to shoot them: prone position has targets of diameter 4.5 cm. (1.8 inches) and the standing position has targets of 11.5 cm. (4.5 inches). Depending on how many targets are left standing after five shots, extra penalties are given to each competitor. The penalty is in the form of extra time (1 minute per missed target) added to the competitor's time, or extra distance (150 meters (490 feet) per missed target) that the competitor must ski through. The winner is the one with the shortest time through the course.

In competitions between 1958 to 1965, high-powered military cartridges such as .30-06 Springfield and 7.62x51 mm. NATO were used, along with military rifles. After 1965, some competitors began to use smaller calibers and lighter rifles, and by 1978, the .22 LR cartridge was adopted as the standard. Separate contests in Norway still use large-caliber military rifles though.

These days, modern biathlon rifles are precision instruments, which are crafted to very high standards.

A modern Biathlon rifle. Click on the image to enlarge. Image courtesy of Eberlestock.

The rifle must weigh at least 3.5 kg. (7.7 lbs.) without ammunition and magazines. It must use .22 LR cartridges and magazines should contain 5 cartridges. Some events allow carrying 3 extra cartridges in the stock, which must be loaded manually, should the competitor miss some shots. The rifle must use bolt action or straight-pull bolt action and no automatic or semi-automatic rifles are allowed. The sights are manual peep sights and no telescopic sights are allowed. The rifle may have a flip up cap at the muzzle, which can be flipped to prevent snow and rain entering the barrel, while the competitor is skiing. The sling of the rifle may be attached to a cuff on the competitor's arm before shooting, to provide extra stability. The stock is lightweight and very adjustable to each competitor's requirements.

Each competitor carries the rifle, ammunition and magazines through the entire course. The rifles are only loaded at each shooting range and unloaded before leaving. In competitions before 1978, the target distances were much longer. Before 1966, each range would have a different distance to the target: 100 meters (330 feet), 150 meters (490 feet), 200 meters (660 feet) and 250 meters (820 feet). In 1966, the distance was reduced to 150 meters (490 feet) for all the ranges in the course. In 1978, the distance was further reduced to 50 meters (160 feet) for all ranges, which is the standard currently. Some competitions in Norway still use larger-caliber military rifles and longer distances to target, as per the original sport rules (with some competitions consisting of shooting various targets at unknown distances.)

Rifles are zeroed before the competition starts, but since it takes place outdoors, the wind and temperature may alter where the rifles shoot, and each competitor needs to adjust the sights accordingly. To make things even more complicated, since there are multiple shooting ranges through the course, a competitor might arrive at one range and find severe wind blowing, but travel to the next range and find no wind blowing there, all in the same course. Each shooting range has flags that flap in the wind, so a competitor can look at these and estimate how hard the wind is blowing and its direction and compensate accordingly.

As each missed shot counts as a penalty and adds more time to the competitor's total, it is vital to hit as many targets as possible at each shooting range. This is difficult to do after skiing through a long distance, as each competitor's heart is racing and lungs are pumping due to the exertion of skiing and the cold weather. The racing heart and aching muscles could cause the rifle to shake while aiming at the targets. Therefore, one of the strategies that many competitors use is to slow down as they are entering into each shooting range. This allows them to focus on controlling their breathing and relaxing their muscles a little, before they enter the range. A world-class competitor can enter a range, shoot all 5 targets and then leave in as little as 19-20 seconds or so.

There are still contests held in Norway, that use older standards (such as using military caliber cartridges, different distances to various targets, longer distances, carrying a military pack, skiing through trees etc.) These are true to the original purpose of the biathlon, which was to provide military training to people, for the purposes of national defense in times of war.

Here's a little video that explains the sport of biathlon for beginners. It appears that the person explaining stuff here is not entirely familiar with firearm terminologies, as she refers to clips instead of magazines and bullets instead of cartridges, but the video does explain the basics pretty well.

Happy viewing!

The AR-7 Survival Rifle

A few months ago, we had discussed the amazing Soviet Space Pistol (TP-82), which was designed to be used as a survival weapon in remote areas. In today's post, we will look at a weapon that was designed in the US for a similar purpose. We are talking about the Armalite AR-7, known these days as the Henry Survival Rifle.

The Armalite AR-7 was designed in 1958 by Eugene Stoner, the same gentleman who designed the AR-15 and M-16 rifles. The AR-7 was based on the older AR-5 which was developed as a survival weapon designed to be used by aircraft personnel and carried in emergency kits stored aboard aircraft. The AR-5 was adopted by the US air force, but they only ordered very small numbers, therefore Armalite used some of the tooling that was originally developed for the AR-5 to create the AR-7 for the civilian market. The rifle was released to the civilian market in 1959. It was meant to be used by bush pilots, backpackers, hikers and amateur explorers.

As a bare-bones survival rifle, one of the primary requirements was for the design to be light and portable. Therefore, the AR-7 was made from plastics and aluminium alloys to reduce weight. The rifle was also designed to be compact so that it could fit inside a backpack. Therefore it was designed so that the parts could be disassembled and stored inside the plastic stock!

An AR-7 stored in a disassembled state. Click on image to enlarge.

When the rifle is stowed within its stock, the whole package can float on water! This rifle is designed to use the popular .22 LR cartridge, which is the most commonly available rifle cartridge in the world. It has a semi-automatic action and can hold 8 cartridges within its magazine. The entire rifle weighs 3.5 pounds (about 1.58 kg.) The rifle is also designed to be disassembled without any tools. The stock attaches to the receiver with a long screw bolt and the barrel screws on to the receiver, both of which can be manipulated using just a person's hands.The entire rifle can be assembled or disassembled in about 30 seconds. 

An assembled AR-7 rifle. Click on image to enlarge.

The rifle was designed for an 8 round magazine originally, but there are now other magazines for it that can hold 10, 15, 25 or 50 rounds as well. Accuracy is pretty decent and it can be used to hunt small game animals.

Armalite sold the rights to the design to Charter Arms in 1973. According to some people, Charter Arms didn't manufacture their rifles with the same quality as Armalite and the rifle started to gain a bad reputation during this period. Charter Arms later sold the design to the Henry Repeating Arms company in 1980. The Henry Repeating Arms company slightly revised the design and produced a much better quality version than Charter Arms and after that, the bad reputation it had collected in the previous few years went away.

The version that is now made by Henry Arms has two 8-round magazines stored in the stock (latest versions have 3 magazines). The plastic stock is now made of ABS plastic which is tougher than the original plastic stock and does not crack easily. It is also much more water-resistant than the older stock. The receiver and barrel are coated with teflon for better corrosion resistance

An AR-7 was even featured in the James Bond movie To Russia With Love starring Sean Connery.

How did they name cartridges - II

When we left off in our last post, we saw that cartridges like .45-70 and .50-90 were named based on their caliber and the amount of black powder in it (e.g. .45-70 has a bullet of .45 inches in diameter and 70 grains of black powder). We also saw that if two different bullet weights were available for the same cartridge, then a 3 number scheme was used (e.g. .45-70-405 and .45-70-500, where the 405 or 500 indicates the weight of the bullet in grains). We will continue our discussion in this post.

With the invention of newer smokeless powders, cartridges still retained the same two digit naming scheme as before: e.g. the famous .30-30 Winchester rifle, .32-20 Winchester or the .30-40 Krag, which replaced the .45-70 in US military service. As before, the first number indicates the caliber (e.g. 0.30 inches diameter) and the second number indicates the amount of smokeless powder in grains.

After some years, people began to drop the amount of grains and use the year that the cartridge was introduced instead. For instance, the Springfield .30-06 cartridge. This cartridge's diameter is 0.30 inches and it was introduced in 1906 (from which we get 06) and therefore it was named as .30-06. The .30-06 actually replaced the .30-03, which was, predictably, adopted in 1903.

Some years after that, people began to drop the second number altogether and simply name the cartridge after the caliber and the company that introduced it  (e.g.) .44 Colt introduced by Colt firearms, .32 S&W invented by Smith and Wesson etc. Sometimes they were named after a specific product (e.g.) .45 ACP where ACP stands for Automatic Colt Pistol. Sometimes they were named after specific attributes (e.g.) .38 Special, .44 Magnum, .577 Express etc., where the words Special, Magnum or Express indicate that these cartridges have extra power.

By the 1950s, people also started to name the first number by the groove diameter of the rifle, rather than the bore diameter of the bullet (at least in America). For instance, .308 Winchester, where the bore diameter is 0.300 inches, but the groove diameter is 0.308 inches.

Over in Europe (except for the UK), people generally use the metric system and name cartridges with two sets of numbers separated by an "x". e.g. 7.62x51, 5.56x45 etc. The first number is the bore diameter of the bullet in millimeters (e.g. 7.62 mm., 5.56 mm. etc.) and the second number is the length of the case in millimeters (e.g. 51 mm., 45 mm. etc.). Note that the first number is the bore diameter, not the groove diameter. Therefore, what we call the .308 Winchester in America actually has a bore diameter of 0.300 inches and a groove diameter of .308 inches and the Europeans take the 0.300 inch measurement and convert that into millimeters (7.62 mm.) and use that in their cartridge nomenclature. This system is generally used in the rest of the world as well (Asia, Africa, South America, Oceania etc.)

The British tend to name their cartridges in American fashion, e.g. .244 H&H Magnum (where H&H stands for Holland and Holland, a famous British firearms firm), .455 Webley (invented by Webley, another British firearms manufacturer) .700 Nitro Express etc. The numbers indicate the diameter of the bullet rather than the groove diameter though.

These are generally the naming schemes in vogue these days, but there are exceptions to the rule. American manufacturers in particular, tend to add names that sound good to consumer ears: e.g. .22 Hornet, .221 Fireball, .224 Rocket etc. Also, there are cartridges such as the .280 Remington (which actually has a bore diameter of 0.277 inches and groove diameter of 0.284 inches) and the .260 Remington (which actually has a bore diameter of 0.256 inches and groove diameter of 0.264 inches). Remington's marketing people decided that customers like numbers that end in zero better, so they named then .280 and .260 instead.

As you can see, these are several ways how cartridges have been named throughout history.

How did they name cartridges - I

In the world of firearms history, we often see famous cartridge names like .30-30 Winchester, .45 ACP, .30-06 Springfield etc. So how exactly do cartridges get named and is there some meaning behind their naming convention. We will study those in this post.

Bear in mind that cartridges are not always referred by the same name throughout history. For example, when Smith & Wesson produced their first revolver model, they made it fire a .22 cartridge, which was then referred to as a ".22" or a ".22 caliber" in 1857, since there were no other cartridges with the same caliber bullet. This cartridge contained 4 grains of black powder in it and a bullet weighing 29 grains (or 2 grams in the metric system) and measuring .222 inches in diameter. In 1871, Smith & Wesson produced another cartridge in .22 caliber diameter. This cartridge used the same 29 grain bullet as its predecessor, but the case was a bit longer than the older one and contained more black powder (5 grains), in order to produce extra power. Therefore, they began to refer to the old .22 cartridge as ".22 Short" and the new one as ".22 Long". Both these cartridges were used for revolvers. Soon afterwards, Remington, Stevens, Winchester etc. started producing the ".22 Extra Long" for rifles and revolvers. This cartridge used a 40 grain (3 gm.) bullet and a longer case that contained 6 grains of black powder in it. Then, the Stevens Arms and Tool Company combined the case of the .22 Long with the 40 grain bullet of the .22 Extra Long to produce the ".22 Long Rifle" (a.k.a. ".22 LR" cartridge).

Public domain image of different .22 caliber cartridges.

The .22 LR became very successful and still remains the most popular cartridge in the present day. Therefore when someone talks about ".22 caliber" in today's world, they are almost certainly referring to the .22 LR cartridge. However, back between 1857 and 1871, when someone said ".22 caliber" they would have been referring to what we now call ".22 short". So you can see how common cartridge designations have changed over the years.

For some early cartridges, they were named with two sets of numbers. For instance, right after the US Civil War, the US government issued the ".50-70 Government" cartridge for use with the Springfield Model 1866 rifle. This was later replaced by the ".45-70 Government" cartridge in 1873. So what do the numbers .50-70 and .45-70 mean? For a ".50-70", it means that the cartridge has a .50 caliber bullet and 70 grains of black powder. Similarly, a ".45-70" has a .45 caliber bullet and 70 grains of black powder. This naming scheme was also used for other cartridges such as the ".50-90 Sharps", ".50-100 Sharps", ".50-110 Winchester" etc.

In some situations, these cartridges were also referred to with three sets of numbers, such as ".50-70-450" and ".45-70-405" where the third number indicated the weight of the bullet in grains. This was done as cartridges of the same size, but with different bullet weights, became common. For instance,  the .45-70 cartridge case was used for two different bullet weights and to tell them apart, the two cartridges were called .45-70-405 and .45-70-500, when the 500-grain-bullet variant was invented in 1884.

In the next section, we will look more into the conventions used to name cartridges.

Cartridges: Rimfire Cartridge

The next type of cartridge we will study is the rimfire cartridge, which was developed around the same time as the pinfire cartridge. The principle of these cartridges is similar to that of the percussion lock (i.e.) use a hammer to strike a blow on some shock sensitive priming material (such as mercury fulminate or potassium chlorate), which then ignites and lights the main gunpowder charge.

The rimfire cartridge was originally developed in the 1830s, but the first practical rim-fire cartridge only came out in 1845 for a .22 caliber ball-bearing (BB) Flobert. This weapon used no gunpowder, but simply used the power of the explosion of the priming material to propel the bullet (which was a spherical ball-bearing). It was only used for shooting clubs since it was a very low powered weapon. The next advancement was due to Smith and Wesson, who produced a popular .22 caliber revolver that used rimfire cartridges in 1857. In fact, this was Smith and Wesson's very first revolver model and the cartridge for this weapon was called the ".22 short" due to the bullet being .22 caliber. Due to the success of the revolver and its ".22 short" cartridge, they soon produced a ".22 long" cartridge in 1871, which was originally intended to be used by revolvers. The ".22 short" and ".22 long" use the same bullet, but the ".22 long" is in a longer case and contains about 20% more gunpowder. A separate manufacturer (J Stevens Arms & Tools Company) took the ".22 long" and added a longer (and heavier) bullet to make a rifle cartridge called the ".22 Long Rifle", popularly known as the "22LR". Even though rimfire cartridges were produced in other larger calibers, the .22 caliber is the one that has been the most successful. The success of the ".22 long rifle" cartridge can be seen in that it is still in production to this present day and is the most common rifle cartridge. In fact, almost every weapons manufacturer of cartridge weapons in the world makes at least one model that uses the 22LR.

In a rimfire cartridge, the gunpowder or propellant is inside the main body of the cartridge, but the primer material (i.e. the shock-sensitive material) is placed throughout the rim at the base of the cartridge:

Public domain image courtesy of wikipedia.com

To fire this, one must strike the rim of the cartridge with a sharp blow. The shock-sensitive chemicals inside will detonate with the force of the blow and spread the flame throughout the gunpowder, thereby discharging the bullet.

In a typical rimfire weapon, there is a spring loaded hammer that is pulled back against spring pressure. When the user pulls the trigger, the hammer is released and forcefully strikes the cartridge, as shown in the figure below:

The hammer is positioned in such a way that it strikes the rim part of the cartridge alone. This design provides a very tight seal, so that excess gas cannot escape through the back of the weapon. Note that the material on the rim of the cartridge has to be somewhat thin so that it can be deformed by the hammer to detonate the cartridge.

To load the weapon, the user merely opens the breech, takes out the old fired cartridge (if it exists) and replaces it with the new cartridge. Unlike a pin-fire cartridge, there is no need to position the cartridge in a special way, as it is symmetrical and the priming compound is present around the entire rim of the cartridge.

Advantages of this cartridge are many:

1. It is a very cheap type of cartridge and ideal for mass production. In fact, it in the early 2000s, it only cost $10 to buy a box of 500 "22 long rifle" cartridges. This makes rimfire weapons a favorite of shooters on a budget.
2. Unlike a pinfire cartridge, the rimfire cartridge does not need to be positioned specially in the weapon.
3. Gas seal is relatively tight, so gas does not escape through the back of the weapon.

Disadvantages:

1. This cartridge needs a thinner case at the rim so that the hammer can deform the case and detonate the priming material. This means that the cartridge itself cannot withstand too much pressure and can only be used for low-powered weapons.
2. Once the cartridge is fired, the cartridge cannot be reloaded at home, due to the deformation of the rim.

Due to the low-power nature of the cartridges, weapons that fire them have less recoil. Hence, they are ideal for training beginning shooters. They are also used by air marshals aboard aircraft, since they have less chance of piercing the aircraft skin.

Conversely, due to the low-power nature of this type of cartridge, rimfire cartridges of larger calibers (such as .44, .41 etc.) were quickly replaced by centerfire cartridges, which we will study about in the next post in this blog. This is because centerfire cartridges can withstand higher pressures and are more suitable for high powered guns.

Rimfire cartridges are still manufactured to this present day, mostly the .22 short, .22 long, .22 long rifle (22 LR) and the Winchester .22 magnum. In most cases, when people say "22 caliber", they are referring to the "22 long rifle" which is the most common variant. Two new rimfire cartridges in .17 caliber have also been introduced in 2002 by the Hornady Manufacturing Company and they've been fairly popular, judging by the sales of these cartridges and the fact that other companies besides Hornady are now beginning to manufacture these cartridges. It appears that rimfire cartridges will stay around for a long time