About History: Guns 'n' Bullets

The first guns  

The first firearms appeared on the battlefields of Europe while knights and Men-at-Arms were wearing plate armour. Contrary to what some might think, both continued to be used alongside each other for centuries. Scroll forward to the Napoleonic Wars of the 19th century and one will discover French cuirassier were still armoured in back and breast plates that were proofed (tested for protection) against musket balls. So, the idea that the introduction of firearms made the wearing of body armour redundant is a fallacy. While it is true that for the most part soldiers in the large armies of the 17th up to the mid-20th century did not wear body armour, such is now a thing of the past where the mass adoption of ballistic armour is commonplace in armed forces of wealthier countries.

The first gunpowder weapon appeared in China sometime during the 12th century AD but did not see widespread use in the region until the 13th century. These early weapons were essentially strong metal cylinders, plugged at one end to form a breech, that fired projectiles using the explosive pressure of gunpowder. A measured charge of powder, either loose or in bag or similar container, is loaded into the tube from the open end followed by the projectile, typically a ball. Wadding may be used to tamp the gunpowder in the ‘powder chamber’ at the breech end against which the ball is rammed down the barrel. To ignite the main charge, a small ‘vent hole’ (or ‘touch hole’) is drilled at the breech end of the tube. Either fine, loose powder is poured into and onto the vent hole or a piece of prepared fuse is inserted into the hole. Igniting this gunpowder (or fuse) flashes burning powder through the vent hole into the breech setting off the main charge. The pressure generated by the resulting explosion propels the projectile along the barrel at high speed toward the intended target.

Possibly as early as the 13th century, but definitely from the 14th century onward, breech-loading cannon appeared. These were still relatively simple designs, but they allowed gunners to pre-prepare a charge in a removable wrought iron ‘pot’ know as a breechblock. Once loaded the breechblock would be married to the rear end of the gun tube and secured firmly in place with wooden wedges (see below).

Handheld guns

During the Middle Ages, large and small cannons were developed for siege and field battles. The cannon replaced prior siege weapons such as the trebuchet. Alongside the larger cannon were the first ‘handgonnes’ or ‘gonnes’, which became fairly common around AD 1400. These guns were essentially handheld cannons comprising a smaller diameter tube that the user loaded with gunpowder and a ball and lit from the outside. For the hand cannon to develop into a more useful tool required two technological improvements. Firstly, the early hand cannons (below left) were simply held in one hand, perhaps with the wooden stick couched in the armpit (below centre and right) or resting on the shooter’s shoulder. Secondly, the gunner had to ignite the powder charge with a handheld burning match which they manually applied to the vent hole. Neither arrangement guaranteed great accuracy, so firearm design needed to evolve a more ergonomic shape and a more reliable ignition system.

The Complete Gun

The year 1817 saw the introduction of the expression ‘lock, stock and barrel’ to mean ‘whole’ or ‘complete’. It derives from the principal parts of a firearm namely:

•  The lock or firing mechanism (complete with the trigger).

•  The stock, or the wooden parts of the gun (sometime now referred to as the ‘furniture’), that give the firearm its ergonomic shape making it easy to hold.

•  The barrel whether smooth bore or rifled (more of which later).

Stocks often require intricate carving to accept the barrel and the lock. Gunsmiths had to ensure the fit and finish were accurate so that the components functioned correctly and reliably. A complete gun might also include several decorative brass fittings such as a butt plate or the barrel bands securing the stock, as well as a ramrod and a ramrod holder underneath the barrel.

The Matchlock

As mentioned, the lock is the ignition mechanism for a firearm whether it uses gunpowder or a pre-assembled complete cartridge. The matchlock, for example, was simply a piece of slow-burning rope lit ahead of time that when touched to the gunpowder filling the vent hole would ignite the main charge. The first ‘handgonnes’ were fired in this way. In the image above centre, the gunner furthest left is using a linstock to securely hold the match and fire his gun. The linstock’s use has the added safety benefit of placing some distance between exploding gunpowder and the gunner’s hand.

The next significant advance was the ‘arquebus’, a long gun that began appearing in Europe and the Ottoman Empire during the 15th century [1]. The addition of a shoulder stock, priming pan, and matchlock mechanism turned the arquebus into a handheld firearm and the first to be equipped with a recognisable trigger. Now an infantryman armed with an arquebus (the ‘arquebusier’) could attach a slow-burning match to a lever (the ‘serpentine’) which, with the press of his finger, could be rotated downward to touch the match onto the priming pan. The introduction of the early trigger made the matchlock somewhat safer to use and with two hands on the weapon meant a steadier platform improving accuracy. Yet, the matchlock still had several problems:

•  The match still had to be lit ahead of time.

•  Even though slow-burning, the match could burn out if there was a long interval between lighting it and firing the gun.

•  A glowing match can be seen at night.

•  Wet weather could extinguish the match or dampen the gunpowder to such an extent that it would not ignite.

Despite these drawbacks, matchlocks remained in common use for 200 years because they were a better option than lighting gunpowder by hand and they were cheap to build.

The Wheellock

At the time of the English Civil Wars (1642 - 1652) a new form of ignition appeared on the battlefield. Developed in Europe around 1500, wheellock firearms were used alongside matchlocks and later the snaplock (1540s), the snaphance (1560s) and the flintlock (c. 1610s).

The wheellock works by spinning a spring-loaded steel wheel against a piece of iron pyrite to produce intense sparks. As described earlier, the sparks ignite gunpowder in a priming pan which flashes through a vent hole to ignite the main charge in the firearm's barrel. The iron pyrite is clamped in vice jaws on a spring-loaded arm known as a ‘dog’. This rests on the priming pan cover. When the trigger is pulled, the pan cover is opened and the wheel is rotated, with the pyrite pressed into contact creating sparks.

The advantage of a wheellock is that it can be pre-prepared and kept ready for instant firing. Unlike a matchlock which, because it must have a burning cord of slow match ready, demands the shooter's constant attention and two-handed operation, the wheellock can be used single-handedly. Conversely, the complexity of the wheellock mechanism made them relatively costly. Wheellock firearms were used alongside matchlocks until both were replaced by the simpler and less-costly flintlock.

The Flintlock

Flintlock is a general term for any firearm that uses a flint-striking ignition mechanism. The first such weapons appeared in Western Europe in the early 16th century. Gradually they replaced earlier firearm-ignition technologies, such as the matchlock, the wheellock, and earlier flintlock mechanisms such as snaplock and snaphaunce. By the late 17th century, the flintlock had proven easier to manufacture, relatively inexpensive, fairly weatherproof and, most importantly, provided an instant and reliable way of igniting gunpowder in a gun’s chamber. Once again, a spark was needed to ignite the gunpowder in the priming pan to set off the chain reaction that fired the projectile. To create the spark, the flintlock adopted the tried and tested ‘flint and steel’ method that had been used to light fires for centuries. In essence, the idea is straightforward. Flint is an amazingly hard form of rock which, if struck against iron or steel, flakes off tiny particles of the metal. The force of the blow and the friction it creates actually ignites the iron, which burns rapidly to form iron oxide (Fe3O4). These hot sparks of burning iron are all that is needed to ignite gunpowder.

For a flintlock to work requires:

•  A ‘cock’ (hammer) with turnscrew that tightly clamps a sharp piece of flint, itself held in a leather patch.

•  A mainspring to power the hammer.

•  A steel priming pan lid, or frizzen, that the flint strikes to create sparks.

•  A priming pan where a small quantity of finely ground gunpowder waits to be ignited by the hot sparks.

To load, the cock is pulled backward to the ‘half-cock’ position which engages a sear in a safety notch that prevents accidental firing [2]. As before, the shooter loads the gun, usually from the muzzle end, with black powder from a powder flask. This is followed by a round lead ball usually of a slightly smaller diameter than the barrel. Balls were often wrapped in a piece of paper or a cloth patch to ensure a tighter fit and prevent the ball rattling along the barrel when fired. Were the ball to do so, then accuracy is degraded significantly. The ball is rammed down the barrel and tamped on the powder charge with a ramrod that is typically stored beneath the barrel. Wadding between the charge and the ball was often used in earlier guns. The priming pan is primed with a small amount of very finely ground gunpowder and its hinged lid, or frizzen, is closed. The gun is now ‘primed and loaded’.

To fire, the cock is rotated backward once more from ‘half-cock’ to ‘full cock’, releasing the safety sear. The shooter raises the firearm to rest the butt in his shoulder and takes aim. Pulling the trigger releases the sear and sear spring engaged in the ‘tumbler’. This causes the tumbler to release the power of the mainspring which is in turn transmitted to the cock [3]. Once released, the cock holding the flint snaps forward striking the spring-loaded frizzen [4] covering the priming pan, opening it and exposing the priming powder. Contact between the flint and frizzen produces a shower of sparks that are directed into the priming pan. The sparks ignite the gunpowder which flashes through a small vent hole (or touch hole) in the barrel that leads to the combustion chamber where it ignites the main powder charge, and the gun fires.

The Percussion Cap

Flintlock firearms continued in common use for over two centuries until eventually replaced by percussion cap in the early-to-mid 19th century and later by cartridge-based systems. The percussion cap was made possible by the discovery of a chemical compound called mercuric fulminate or fulminate of mercury (Hg(ONC)2) a compound of mercury, nitric acid and alcohol. Mercuric fulminate is extremely volatile and shock sensitive such that a sharp blow can cause it to detonate. By putting a small amount in a tiny cup (about the size of a pencil eraser; see below right) known as a cap and affixing this to a nipple, which has a tube leading into the barrel, the cap’s detonation can ignite gunpowder in the barrel.

The percussion lock is identical to the flintlock in terms of the mainspring, hammer, tumbler, sear and sear spring making it easy to convert flintlocks to the new mechanism. As with the flintlock, the hammer can be uncocked, half-cocked or fully cocked, but what the percussion lock does not have is the flint and frizzen. Instead, hammer is shaped to strike the cap on the nipple. This made the percussion lock easier to load, more weather resistant and more reliable meaning that by the time of America's civil war, both Union and Confederate armies used percussion-cap guns. Even so, the percussion lock did not last very long, perhaps 50 years. Firearms technology and manufacturing processes were developing rapidly, and it quickly became possible to integrate the cap, powder and projectile into a single metal cartridge at low cost.

Cartridges

The first cartridges appeared in the second half of the 16th century. These were charges of gunpowder wrapped in paper; the projectile, a lead ball, was loaded separately. During the next century, methods of combining the ball with the powder were devised. In muzzle-loading a musket, the shooter bit off the end of the paper cartridge, poured a small amount of the powder into the priming pan, then poured the rest down the barrel. The ball, inserted into the barrel followed by the paper cartridge as wadding, was rammed down onto the powder at the breech end. In the 19th century breech-loading rifles and various multi-shot weapons were introduced. These necessitated loading an entire cartridge as one unit yet still required an external spark to ignite the propellant. 

In 1846 a Paris gunsmith, Benjamin Houllier, patented an improved design for the pinfire cartridge, capable of being fired with a strike from the gun’s hammer. In one type, a pin was driven into the cartridge by the hammer action; in the other, a primer charge of mercuric fulminate was exploded in the cartridge rim. Later improvements changed the point of impact from the rim to the centre of the cartridge, where a percussion cap was inserted. The cartridge with a percussion cap, or cup, centred on the base of the cartridge (known as ‘centrefire’) dominates larger calibres, but rimfire cartridges remains popular in small-bore, low-powered ammunition, e.g., .22 calibre. The invention and introduction of smokeless nitrocellulose powder in the late 19th century replaced black powder as the favoured propellant. With this change came the birth of the modern cartridge, which typically integrates the primer, propellant, and a projectile (bullet) into each metal case (usually brass, but sometimes steel is used).

Gun Barrels

The first cannon barrels were made by forming several longitudinal staves into a tube by beating them around a mandrel (a long rod of the desired diameter) and forge welding them together. The tube was then reinforced with a number of rings or sleeves - in effect, hoops similar to those used in coopering wooden barrels, hence the shared name. The hoops were forged with an inside diameter about the same as that of the outside of the tube. Each hoop was raised to red or white heat, then slid into place over the cooled tube where they were held firmly in place by thermal contraction. The sleeves or rings were butted against one another and the gaps between them sealed by a second layer of hoops.

Wrought-iron breechloaders  One particular problem was forging a strong, gastight breech. One solution was to weld a tapered breech plug between the barrel staves. Partly because of the difficulties of making a long, continuous barrel, and partly because of the relative ease of loading a powder charge into a short breechblock, gunsmiths soon learned to make cannon in which the barrel and powder chamber were separate. As the charge and projectile were loaded into the rear of the barrel, these were called ‘breechloaders’. As shown above, the breechblock was mated to the barrel by means of a recessed lip at the chamber mouth. Before firing, it was dropped into the stock and by hammering a wedge behind it was forced forward against the barrel’s chamber. After the weapon was fired, the wedge was knocked out and the breechblock removed for reloading. This scheme had significant advantages, particularly in the smaller classes of naval swivel guns and fortress wall-pieces, where the use of multiple breechblocks permitted a higher rate of fire.

Cast bronze muzzle-loaders  The advantages of cast bronze for constructing large and irregularly shaped single piece objects were well understood from sculpture and bell founding. As a process for making gun barrels a number of problems had to be overcome. First off, bronze is an alloy of copper and tin that foundries had to ensure could withstand the shock and huge pressures involved in firing. Early techniques produced bronze alloys that were prone to internal cavities and ‘sponginess’, which was not much of a problem for casting statues but for cannons could result in catastrophic failure. By the first decades of the 15th century, and, by the 1420s and ’30s foundry practices had developed sufficiently to overcome the technical problems of the inherent deficiencies of the metal.

Handheld firearms  By the time flintlocks appeared, blacksmiths would beat a flat piece of iron into a cylinder around a mandrel. Heating the iron to a high enough temperature in a forge meant the blacksmith could forge weld the seam along the length of the barrel to form a strong tube, a process that could take days. Drilling out the tube with successively larger bits and then polishing with a reamer creates a smoothbore barrel, which could range in length from 15 to 30 cm (6 to 12 inches) for pistols and 102 to 152 cm (40 to 60 inches) for long guns.

Earlier pistols and muskets (arquebus, matchlock and flintlocks) were ‘smoothbore’ which, as the name implies, were smooth along the entire length of the barrel. Most, but not all, shotguns are made this way as was the British Army’s famous ‘Brown Bess’ smoothbore flintlock musket [5]. The problem with these firearms is their lack of accuracy at range. In 1811, for example, a test of accuracy conducted in London produced the following results: at 100 yards (91 m) the musket hit the target 53% of the time. At 200 yards (180 m) the number of hits had dropped to 30%, and at 300 yards (270 m) only 23% hits were achieved. Even so, the accuracy of the Brown Bess was in line with most other smoothbore muskets of the 18th and 19th centuries.

Rifling a barrel is a way of increasing the accuracy of the bullet, whether spherical or cone shaped. Starting with a smooth bore barrel, helical grooves are machined into and along the internal (bore) surface of a gun's barrel. As the bullet speeds down the barrel it engages with the rifling’s lands and grooves which impart a spin to the projectile around its longitudinal axis. This has the effect of improving the projectile’s aerodynamic stability and accuracy over smoothbore designs. Straight grooving had been applied to small arms from at least 1480, but these were originally intended as ‘soot grooves’ to collect gunpowder residue. True, helical rifling dates from the 16th century, but gunsmiths had to engrave the grooves by hand making it a laborious and expensive manufacturing process. Consequently, rifling did not become commonplace until the mid-19th century. Even so, rifles were not popular with military users still muzzle-loading their firearms because they were difficult to clean, and loading projectiles presented numerous challenges. If the bullet was of sufficient diameter to engage the rifling, then ramming it down the bore became much harder. Yet, if the diameter were reduced to make loading easier, then the bullet would not fully engage the rifling and accuracy was reduced.

Endnotes:

1. The exact dating of the matchlock's appearance is disputed. It could have appeared in the Ottoman Empire as early as 1465 and in Europe a little before 1475.

2. Were the safety sear to fail then the gun could go off ‘half-cocked’ and unexpectedly fire.

3. The mainspring presses against the tumbler and can rotate the hammer with a great deal of energy. The sear engages the tumbler when the gun is cocked and resists the force of the mainspring. When the trigger is pulled, it pushes the sear enough to release the tumbler and allows the hammer to drive the flint forward.

4. The frizzen spring securely holds the cover attached to the frizzen over the priming pan. This arrangement has two benefits: firstly making the flintlock more weatherproof, and secondly, reducing the risk of the priming powder accidentally igniting - literally a ‘flash in the pan’.

5. ‘Brown Bess’ is a nickname of uncertain origin for the British Army's muzzle-loading smoothbore flintlock Land Pattern Musket and its derivatives. The musket design remained in use for over a hundred years with many incremental changes in its design. These versions include the Long Land Pattern, the Short Land Pattern, the India Pattern, the New Land Pattern Musket and the Sea Service Musket.