Sunday, March 30, 2014

Ancient Techniques of Rifling Machines - I

In the last few posts, we studied some videos of rifling techniques and we had also studied the descriptions of these techniques in detail many months earlier. The thing to note though is that all these videos showed relatively modern machinery making the rifling. In fact, the oldest machine in those videos dates to some time in the early 1900s. However, as we have seen earlier, the history of rifling dates back to about 1520, well before such automated rifling machines were invented. So how did people historically cut rifling grooves into their barrels, without the aid of modern machinery? We will attempt to reconstruct their techniques in the next series of posts, only using technologies that would have existed in the 1500s and 1600s. As we are studying the techniques, it will become fairly obvious to the reader, that historical gunsmiths would have had some pretty good skills in both woodworking and metalworking, which is why they formed separate gunsmithing guilds, which were different from carpentry and blacksmith guilds.

The first tool that any gunsmith would have used would have been a lathe. This handy tool was known to the ancient Egyptians in 300 BC and later spread to the Greeks, Indians, Chinese, Assyrians, Romans etc. The first design simply had one person alternately pulling on two ends of a rope looped around a wooden work piece, to rotate the work piece around two centers, and the other person would apply a sharp edged tool to the rotating wooden piece, to cut it into a cylinder or a tapered cylinder or a similar shape.

The following image can be found in a bas-relief carving at the tomb of Petosiris, a high priest who lived in Hermopolis, Egypt, dated to about 300 BC.

Two images of lathes, as used in ancient Egypt

The basic two-person operated lathe concept was modified by other cultures, as shown in the example from India below:

Horizontal two person lathe used in Ancient India.

The Romans came up with a lathe design that used a bow to turn the wooden work-piece. With this type of lathe, there is no need for a second person, as a single person can move the bow with one hand and manipulate the cutting tool with the other hand. However, there is lesser power applied, since the person is turning the work piece with only one arm and hence it is suitable for smaller jobs only.

The bow lathe design stayed with us for quite a long time: small bow lathes were still used by clockmakers in the early 1800s.

In the middle ages, someone got the idea of tying one end of the rope to a thin springy pole or branch and the other end to a foot pedal and the rope would loop around the wooden work piece to be turned. The craftsman would use his foot to operate the pedal and use his two hands to hold various tools against the turning wood piece.

Spring pole lathes from the middle ages

The above illustrations show some spring pole lathes from the middle ages. The left side illustration is based on a Parisian manuscript from the 13th century. As with bow lathes, spring pole lathes do not need for a second person to turn the wood piece. Spring pole lathe designs were commonly used for hundreds of years, all the way to the early part of the 20th century!

Other lathe designs included using horses, flowing water, steam and electricity to power them and lathes evolved to cut both wood and metal pieces.

Wednesday, March 26, 2014

Videos: Flow Forming

In our last post, we looked at a few videos showing how hammer forging works. In today's post, we will revisit another technique to manufacture rifling that we studied several months ago: flow forming. To refresh your memory, here's a link to that original post describing flow forming.

This is a relatively new technique and therefore there don't appear to be any videos on youtube specifically showing this process being used to make gun barrels. However, there are videos showing how a flow forming machine is used to form tubes, which is close enough for our purposes to understand the principles behind this method.

Happy viewing.

Tuesday, March 25, 2014

Videos: Hammer Forged Rifling

In our last post, we looked at a couple of videos showing how button rifling works. This is a technique we had studied many months ago. In today's post, we will revisit another technique that we had studied back in May 2010, hammer forged rifling. To refresh your memory, here's a link to the original post, describing the process of hammer forged rifling.

Now that you've read that post, let us watch a couple of videos showing the process in action. First up, we have a short video from Daniel Defense, a well known manufacturer of firearms and firearm parts here in America. While many American manufacturers prefer to use button rifling to make their barrels, Daniel Defense uses hammer forging machines.

As we mentioned in the original post, hammer forged rifling is much more prevalent in Europe than America. Here's a couple more videos of the process, from European manufacturers. The next video is from Armalon UK:

And finally, we have another video about the process, as done by the Steyr Mannlicher factory in the town of Steyr, Austria. Incidentally, the leading manufacturer of hammer forging machines in the world is an Austrian company called GFM GmbH, which is also located in the town of Steyr! It is interesting to note that Steyr Mannlicher actually uses a slightly different process to make their barrels, than most other manufacturers of hammer forged barrels. The following video describes their process and also how they do some things differently than other companies.

Happy viewing!

Monday, March 24, 2014

Videos: Button Rifling

In our last post, we looked at a video showing broach rifling in action, a subject we had studied many months ago. In today's post, we will revisit the process of button rifling. We had studied this process many months ago, here on this forum. In order to refresh your memory, here's a link to that original post describing the process of button rifling.

Now that you've read about the process, let's look at a movie displaying the process in action:

The movie above shows the process of button rifling a barrel, using a button that is pulled through the barrel. Notice how the chuck on the left rotates the barrel, as the button is being pushed through.

In the original article about button rifling that we linked above, we mentioned that there are two different ways for the button to be used. The button can be either pulled through the barrel (like the video above shows), or it can be pushed through the barrel, as the following video shows:

Note that in the second video, the barrel is not rotated as the button is pushed through. Instead, the button rotates as it is being pushed through the barrel.

Happy viewing!

Sunday, March 23, 2014

Videos: Broach Rifling

In our last post, we looked at some videos about cut rifling, a process we'd studied many months ago. In today's post, we will study another method of cutting rifling which we'd also studied back in May 2010. Today, we will look at a video that demonstrates broach rifling. The purpose of this series of posts is to add movies to the description of the processes, so that the reader can get an idea of how things work.

If you've not already read the description of the process of broach rifling, here's a link to that article again: Rifling: Manufacturing: Broach Rifling.

Now that you've read about the process, let's look at a movie demonstrating the process in action:

This video comes to us from a company called Miles Broaching, a manufacturer of broaching tools for several applications. In the above video, they demonstrate using a broaching tool to produce rifling for a handgun barrel. As you can see, the process happens pretty quickly, much faster than the cut rifling process we studied in the previous post.

Friday, March 21, 2014

Videos: Cut Rifling

Four years ago, in the early days of this blog, we had studied a method of manufacturing a rifled barrel, called Cut Rifling, or more accurately, Single Point Cut Rifling. Since then, that series of posts has been referenced by other websites which wish to explain how these technologies work. However, mere descriptions of the processes involved is not always enough. Hence, the next series of posts will present movies of the various processes.

If you don't know how cut rifling works, you should click on the links above and read up on the processes. Then, watch the following movie to see it in action:

The sine bar rifling machine in this video was manufactured by Diamond Machine Corp. of Rhode Island. This company was originally founded by Mr. R.I. Costain and Mr. Nicholas B. Hadley in 1869 and known as Hadley & Costain, manufacturers of the Diamond Emery Wheel. In 1881, they shortened their name to Diamond Emery Wheel & Machine Corp., and around 1889 or 1890, they became known as Diamond Machine Corp and they seem to have been in business till at least 1926.

The uploader of this video notes that this machine had been owned by multiple people, including the uploader's grandfather and has been restored to working condition and is cutting its first barrel in 40 years.

As was mentioned in the original cut rifling thread referenced above, these machines are not being manufactured in quantity, as they were before World War II. Therefore, it is hard to find a machine for sale these days and hence, some people manufacture their own versions, usually by converting a lathe.

The above video shows a person cutting rifling using a small lathe and a home-made cutting tool, which produces a fairly good product.

The next video shows a person cutting rifling using a more manual method:

It just goes to show that when the technology is not available, people can still get their work done, using a little ingenuity.

In the next post, we will look at a video about broach rifling. Until then, happy viewing.

The Enouy Revolver

In our last post, we studied a very unusual firearm, the Girandoni Repeating Rifle, which did not use any gunpowder, but was entirely powered by air pressure. In today's post, we will study a very unusual revolver design, the Enouy Revolver. One look at it is sufficient for the reader to judge how unusual this is:

The Enouy Revolver. Click on image to enlarge.

The Enouy revolver was a design patented by Joseph Enouy of Middlesex, England, who received British patent #1359 in 1855. The basic revolver was based on a transitional revolver design made by Charles Osborne in 1845. The innovative part of Enouy's design was the compound magazine design. According to the notes for his patent application:

Patent 1359. Joseph Enouy, of 31, Denbigh-place, Pimlico, St. George's, Hanover Square, Middlesex, for The means of removal of every rotary or revolving barrel or cylinder containing chambers from all revolver pistols, guns, and fire-arms, and the substitution in their place by another and other barrels or cylinders in succession.

Two or more revolving breech-pieces are connected in a frame attached to the stock in such a manner that when the charges in the chambers of one breech-piece have all been fired, the breech-piece may then be removed and others ready charged by successively substituted in its place.
 - Dated June 14, 1855. Sealed December 11, 1855.

In this particular example, each revolver cylinder is capable of holding 6 shots and there are 8 different revolver cylinders attached to the compound magazine wheel, thereby giving this weapon a capacity of 48 shots. Here's another view of the same firearm:

Enouy Revolver. Click on image to enlarge.

The magazine wheel rotates around a rod, which is fastened to the revolver butt on one end and to a bracket that is attached to the underside of the revolver on the other end.

As you may have guessed, this weapon is very heavy, unbalanced and unwieldy at the same time. Due to the magazine wheel in front, the user can't carry this revolver is his pocket or in a holster either. This firearm design was not a success and Joseph Enouy didn't seem to manufacture many of them either. In fact, most of the pictures of this firearm available on the web are from one particular revolver made by Enouy, which was once owned by a Mr. Vokes. As there are no records of this revolver being manufactured and sold commercially, it is possible that the above example is literally the only one that was ever made. It is fortunate that we have a record of Mr. Enouy's patent application available.

Monday, March 17, 2014

The Girandoni Repeating Air Rifle

In our last post, we looked at the Cookson Repeater. In today's post, we will look at another repeating rifle, but this one has a number of very unusual features of interest. Today's study will be about the Girandoni Repeating Air Rifle.

The Girandoni Air Rifle was developed by an Italian gunsmith and watchmaker named Bartholomaus Girandoni around 1778 or 1779 in the Tyrol region of Italy. In 1780, it was adopted for use in the Austrian army, where it was called a Windbuchse (literally meaning "wind rifle" in German). The rifle was in use by the Austrian military until around 1815 and was used against in battles against the Turks. Japan and France were also other users of this type of weapon.

An unusual feature of the Girandoni rifle was that it did not use any gunpowder. Instead, the method of propulsion was compressed air. The rifle was about 4 feet (1.2 meters) long, weighed about 10 lbs (4.5 kg.) and fired a .46 caliber ball at velocities of around 750-900 feet/sec (about 225 - 275 meters/sec), which is about the same velocity as a .45 ACP bullet coming out of a modern Colt 1911 pistol. Although, air rifles had been in existence before Bartholomaus Girandoni invented his rifle, previous models were all single shot rifles, whereas this was the first example of a repeating air rifle.

It looks similar to other flintlock muzzle loaders of that era, but there are some interesting differences. For instance, there is a tubular magazine on the side, where the user can load about 20 spherical bullets. In fact, this was one of the first firearms in history to feature a tubular magazine. There is no flint, frizzen or firing pan, since this weapon doesn't use gunpowder. The stock is a hollow air reservoir made of iron, that is covered in leather and screws on to the back of the rifle

A leather gasket is placed between the rifle and the air reservoir, to maintain a tight seal. In the field, the leather gasket often needed to be wetted to make sure that the seal was good. There is a thumb slide lever on the left side of the rifle that is pushed to load this weapon.

When this rifle was adopted by the Austrian army, each soldier was equipped with three air reservoirs (one attached to the rifle and two spares carried in a leather bag), 100 lead bullets in tubes, spare leather gaskets and an air pump to refill the reservoirs. In addition, each soldier also had a cleaning kit and a bullet mold to cast extra bullets.

Replica of Austrian soldier's kit carried with the Girandoni Rifle. Click on image to enlarge. Public domain image.

To use this rifle, the soldier would point the rifle's muzzle to the sky and push the thumb slide button on the left side of the rifle to open the breech block. Due to gravity, a bullet from the tubular magazine would fall into the breech. The soldier would then cock the rifle and the rifle was ready to fire. One of the nice things about this rifle was that the soldier could load it from behind cover, in a prone position. The soldier would fire his rifle, then roll on his back, point the rifle to the sky and push the lever, then roll back on his stomach and cock the rifle and be ready to fire again. All this would only take a couple of seconds and this was a huge advantage over other muzzle loaders of the era.

The air-reservoir was pressurized to about 800 pounds per square inch (about 5515 kilo-pascals (kPa) for metric speakers). By comparison, a modern automobile tire is typically pressurized to about 35-40 pounds per square inch (or about 240-275 kPa). To achieve this kind of pressure, the user would have to pump it with approximately 1500 strokes using the hand-pump. Since this could take some time, that's why the user was supplied with two extra air reservoirs. A full air reservoir was good for shooting about 30-40 shots, before the pressure would fall below a useful amount and the user would then replace it with another reservoir. The first 10 shots would be lethal to about 150 yards, the next 10-15 shots would be lethal to about 100 yards and the remaining 10-15 shots would be lethal to about 75 yards.

Since the rifle uses no gunpowder, it does not produce much noise, which makes it good for ambushes. There is no smoke produced either. The user also doesn't need to worry about keeping gunpowder dry in rainy weather. However, the weapon has some disadvantages as well. When the weapon was first manufactured, production technology was not as good as it is today and the screw threads around the neck of the reservoir were rather weak. The leather gaskets needed to be constantly kept wet to avoid air leaks. The reservoirs were also not very sturdy and often broke in the field, rendering the weapon useless as a rifle. The reservoirs were also difficult to make with the manufacturing technology available during that time. Filling the reservoirs by hand took about 1500 strokes of the hand-pump to fill each one and this took some time. The Austrian army attempted to fix this by providing larger, more efficient pumps mounted on wagons, but this meant the wagons needed to follow the soldiers around the battle field, thereby limiting their mobility. These are some of the reasons why the Austrian army stopped using it in 1815.

However, this type of rifle has a very important place in American history. A version of the Girandoni air rifle was made in Philadelphia by one Isiah Lukens, who was also a watchmaker and gunsmith like Bartholomaus Girandoni. The Lukens version of the rifle had a capacity of 23 bullets, instead of 20 bullets that the original rifle had. One of these rifles was custom-made by Isiah Lukens for Meriweather Lewis, who carried it with him on the famous Lewis and Clark expedition from 1804 to 1806 (for non-American readers, the Lewis and Clark expedition was a famous scientific and exploration expedition that discovered a land route from the city of St. Louis, Missouri to the west coast of the United States.) Meriweather Lewis is recorded to have used this rifle to impress several Native American tribes, who were all amazed by its repeating capability and the fact that it made less noise than a conventional firearm.

The video below shows the curator of the NRA museum explaining the features and operation of this rifle:

The Girandoni rifle had quite a few innovations. It was one of the first rifles to feature a tubular magazine, well before the Spencer rifle and the Henry repeating rifles, which  were invented around 80 years later. It was the first repeating rifle in the world, that was used in military service. The mechanism it used was also quite advanced for its time. An air rifle even finds mention in the Sherlock Holmes mystery, The Adventure of the Empty House, where Colonel Moran attempts to assassinate Sherlock Holmes, using an unique air rifle made by a blind German mechanic named Von Herder.