Showing posts with label Bira Gun. Show all posts
Showing posts with label Bira Gun. Show all posts

Saturday, August 2, 2014

Early Machine Guns

In our last post, we looked at some basics about machine guns. In today's post, we will study some early developments in machine gun history and what technologies needed to be invented along with them.

One of the early developments in weapons capable of firing multiple shots before reloading was the Puckle gun, which we already studied some time ago. This was invented in 1718 and is the precursor of the revolver.
A Puckle gun. Click on the image to enlarge. Public domain image.

There were also other multi-shot weapons invented later, such as the Mitrailleuse gun and the Belton flintlock, but the first real practical machine gun was the Gatling gun, invented by Richard Gatling in 1861.


In order to have a rapid firing weapon, it was necessary to have a way to automate/quicken the reloading process and the invention of the cartridge came in handy here. Early gatling gun models used paper cartridges and percussion caps, because these were the same technologies used by US Army infantrymen of that era -- in fact, the Gatling gun was designed to use the same caliber cartridges. However, this model was prone to jamming. The second model used the rimfire cartridge instead. Rimfire and centerfire cartridges made the Gatling more reliable. Metallic cartridges also made it possible to provide a better seal in the chamber of the firearm, because the hot gases from a fired cartridge expands the metal case and seals the back of the chamber.

Another technology that made it possible for modern machine guns was the invention of smokeless powder. Early Gatling guns used black powder cartridges. With black powder, the smoke rapidly makes it hard for the operators to see what is going on. On top of that, black powder leaves behind a lot of dirty residue and this can cause the mechanism of a machine gun to jam. Smokeless powders produce a lot less residue, therefore the gun can fire for longer periods without risk of jamming.

Improvements in metallurgical techniques also helped, because it made it possible to make gun parts which perform reliably for extended periods of time and resist heat better as well.

With that said, heat dissipation has always been a problem in machine gun design. In the case of the Gatling gun, the problem was solved by using multiple barrels. With multiple barrels, the weapon can fire at a higher rate, but each barrel is rotated after each shot and therefore has time to cool before it fires another shot. However, the presence of multiple barrels makes the overall weapon heavier. Water cooling and quick-change barrels are other techniques that were historically used by other machine guns to solve the same issue. Interestingly, the use of multiple barrels in a gun was revisited in modern times, with the invention of the minigun and the multi-shot cannon used on the A-10 Warthog aircraft.

Also, the idea of using an electric motor to power a gun is a lot older that most people realize. In fact, in 1893, Richard Gatling received a patent for a gatling gun powered by an electric motor!


Sunday, August 15, 2010

Bira Gun

One of the variants of the Gardner Gun is an interesting weapon called the Bira gun. This was invented by a Nepalese General, Gehendra Shamsher Jang Bahadur Rana and named after the reigning Nepalese monarch of the time, King Prithvi Bir Bikram Shah. It has the distinction of being the last mechanically cranked machine gun ever manufactured.

The history of the Bira has to do with the political situation between Nepal and British India at that time. Under a Nepalese-British agreement, the Nepalese government allowed the British to trade with Nepal and Tibet and allow recruitment of Gurkhas in the British Indian army. In turn, the British agreed to sell firearms and ammunition and a wide variety of armaments to the Nepalese. However, despite Nepalese requests to purchase machine guns, the British declined to do so, because they feared that the Nepalese would clone these (which they already did with some other British origin firearms) and then they would have too many automatic weapons and could challenge British power in India.

Undaunted, the Nepalese set upon building their own machine gun design around 1896-97. Without a background in firearms design, it was decided to start by borrowing a design from somewhere else, in this case, a British model of the American Gardner machine gun. The firing mechanism was essentially the same as the Gardner gun, but there were some other significant differences.


The first difference is that the caliber of this weapon is different from the Gardner gun. Since the Nepalese had already built up a large supply of ammunition for Martini-Henry rifles, it was decided to make their machine gun use the same cartridges as the Martini-Henry (i.e.) the 0.577-450 cartridge.

Unlike the Gardner gun is that the Bira doesn't have a vertical magazine for holding ammunition. Instead, it uses an drum magazine mounted horizontally on top of the barrel. The flat circular drum magazine can be clearly seen in the picture above. The drum magazine could hold up to 120 rounds, in 60 rows of 2 rounds each, one on top of the other. The magazine weighs around 14 kg. when empty and about 19 kg. when fully loaded with ammunition.

Biras were mostly made of iron and steel parts, but the wheels were made of teak wood and brass was used for the wheels controlling the vertical elevation and horizontal traverse, as well as the gearing used for these.

The Bira has twin barrels very much like the Gardner gun, but there is no cooling water jacket around the barrels.

One more curious difference is that the crank is turned backwards (i.e. counter-clockwise) instead of forwards. This was done because the General opined that it was easier to pull instead of push and since pulling is a more natural movement, it is easier to operate the weapon for longer periods without fatigue.

Since Nepal did not have any modern factories during this time, each gun was hand-made. This meant that they could not interchange parts at all. In fact, in some cases, individual screws on a Bira were marked to fit in specific holes! Similarly, the magazines were also numbered to match the serial numbers of specific guns, since they were hand-fitted individually and would only fit in a particular gun. In the above picture, you can see the serial number plate of the gun: it is the oval yellow plate located between the crank and the drum magazine.

Due to the hand-made nature of manufacturing, only 50 or so Bira guns were ever manufactured. These were put into storage and none of them ever saw any wartime service. By then, the Maxim machine gun had been invented and the Bira became obsolete almost as soon as it was made. In the late 1970s, some Bira guns were put on sale in the market and acquired by collectors in the United States. When one was fired in 2009, it was found that it was still pretty accurate once the sights were dialed in. It was also found that in spite of one of the extractors of the gun being damaged, the gun could still fire due to its rugged design!