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The History Of Crossbows Part 1
#40 - 4--naselfdefense--The History Of Crossbows Part 1--2008-10-12 11:43:42
#Welcome to the wonderful world of crossbows.
Before we get started, I'd just to take a moment to say one thing... CROSSBOWS ARE WEAPONS...NOT TOYS! True, crossbows can be fun for kids of all ages, but they can also be very dangerous in the hands of irresponsible shooters. Even the pistol crossbows (while they may seem like a nice little target shooting toy) can cause serious injury or death if you don't treat them with the respect they deserve. That being said, let's get on with our story...
- A crossbow is a weapon consisting of a bow mounted on a stock that shoots projectiles, often called bolts. A mechanism in the stock holds the bow in its fully-drawn position until it is shot by releasing a trigger.
The earliest designs utilized a slot in the stock, down into which the cocked string was placed. This is sometimes called a 'notchlock' crossbow. To fire this design, a vertical rod is thrust up through a hole in the bottom of the notch, forcing the string out. This rod was usually attached to a rear-facing firing lever called a trigger or 'tickler'. A later design, predominant through the end of the 16th century, utilized a rolling cylindrical pawl called a 'nut' to retain the cocked string. This nut has a perpendicular center slot for the bolt, and an intersecting axial slot for the string, along with a lower face or slot against which the internal trigger sits.
Nuts were generally made of antler, bone, ivory or metal (usually brass). A trigger system, (usually made of iron or steel from medieval times onwards), was used to retain the force of the cocked string in the nut and then release the nut to spin, and the string to shoot the bolt. Sophisticated bronze triggers with safety notches are known to have been used on crossbows from ancient China. Complicated iron triggers that could be released with little strength are known in Europe from the early 1400s. As a result crossbows could be kept cocked and ready to shoot for some time with little effort, allowing crossbowmen to aim better.
The crossbow played an important role in the late Medieval period. The crossbow was really the first hand-held weapon that could be used by an untrained soldier to injure or kill a knight in plate armour. The most powerful crossbows could penetrate armour and kill at up to 200 yards.
Crossbows became popular in war for the simple reason that they were easier to aim than longbows. This was because the crossbowman didn't have to use a hand to hold the string back while aiming. On a similar note, a crossbow can be loaded long before the bowman might need to shoot. In this way, the bowman would be able to shoot immediately if surprised. Crossbows did, of course, come with a price. That price is inefficiency, and in the firing rate.
No bow is perfectly efficient, but Medieval crossbows were particularly inefficient. The reason for this is the draw length and the lathe (also called a prod) of crossbows are short. So even though a crossbow may have a great deal of stored energy when spanned, the tips of the lathe do not have enough time to reach the maximum velocity, so the amount of stored energy is not transferred fully to the bolt. It is the lathe tip velocity that determines the speed of the bolt.
This problem could have been alleviated with a longer draw length or a longer lath, but that would increase the weight and bulkiness of the crossbow, which were already distinct disadvantages of the Medieval crossbow.
Crossbows were mainly either weapons of war or sport (hunting and target shooting). The larger war crossbows were used to defend fortifications. Smaller crossbows could be quite effective in open battle when used correctly, but since a crossbowman was particularly vulnerable while reloading the crossbow, he required some sort of defense (a wall or a shield) to be effective in battle.
On a side note: Crossbows were also highly prized by assasins. Assasins were the main users of the smallest crossbows, as they were more easily hidden and transported.
The bow (called the "prod" or "lath" on a crossbow) of early crossbows were made of a single piece of wood. Composite bows were made from layers of different material—often wood or horn —glued together and bound with animal tendon. These composite bows, made of several layers, are much stronger and more efficient in releasing energy than simple wooden bows. As steel became more widely available in Europe around the 14th century, steel prods came into use.
The crossbow prod is very short compared to ordinary bows, resulting in a short draw length. The resulting thick prods are less efficient at releasing energy, but more energy can be stored by a crossbow. Traditionally the prod was often lashed to the stock with rope, whipcord, or other strong cording. This cording is called the bridle.
The strings for a crossbow are typically made of strong fibers that would not tend to fray. Whipcord was very common; however linen, hemp, and sinew were used as well.
The problem when handling early crossbows was the comparably short draw length and the great amount of energy needed to draw them. Some crossbows had prods of up to 800 pounds of draw, if not more. Draw-weights of 500 pounds were common.
Some light crossbows could be drawn by hand, but for others the help of mechanical devices was needed. The simplest version of a mechanical cocking device was a hook attached to a belt, drawing the bow by straightening the legs. Other devices were hinged levers which either pulled or pushed the string into place... cranked rack-and-pinion devices called 'cranequins'... and multiple cord-and-pulley devices called windlasses.
Modern recurve crossbow:
One advancement to the crossbow (and longbows also) was the invention of the recurve bow. A recurve crossbow is a bow that has tips curving away from the archer. The recurve bow's bent limbs have a longer draw length than an equivalent straight-limbed bow, giving more acceleration to the projectile and less hand shock. The only disadvantage was that recurved limbs put greater strain on the materials used to make the bow, and they may make more noise with the shot.
Enter the Compound bow:
A compound crossbow is a modern crossbow, and similar to a compound bow, The limbs are usually much stiffer than those of a recurve crossbow. This limb stiffness makes the compound bow more energy efficient than other bows, but the limbs are too stiff to be drawn comfortably with a string attached directly to them. The compound bow has the string attached to pulleys, one or both of which has one or more cables attached to the opposite limb. When the string is drawn back, the string causes the pulleys to turn. This causes the pulleys to pull the cables, which in turn causes the limbs to bend and thus store energy. The use of this levering system gives the compound bow a characteristic draw-force curve which rises to a peak weight and then "lets off" to a lower holding weight.
Bolts:
The arrow-like projectiles of a crossbow are called bolts. These are much shorter than arrows, but can be several times heavier. There is an optimum weight for bolts to achieve maximum kinetic energy, which varies depending on the strength and characteristics of the crossbow. In ancient times the bolts of a strong crossbow were usually several times heavier than arrows. Crossbow bolts can be fitted with a variety of heads, some with sickle-shaped heads to cut rope or rigging... A highly specialized type of bolt can be employed to collect blubber biopsy samples used in biology research... But the most common today is a four-sided point called a quarrel, or a straight steel tip (generally used for target shooting)
Crossbows could be adapted to also shoot stones or lead bullets. Primarily used for hunting wildfowl, these usually have a double string with a pouch between the strings to hold the projectile.
HISTORY OF CROSSBOWS:
It's not clear exactly where and when the crossbow originated, but there is evidence that it was used for military purposes from the second half of the 4th century BC onwards.
The earliest Chinese document mentioning a crossbow is in scripts from the 3rd - 4th century BC attributed to the followers of Mozi. Sun Tzu's influential book The Art of War (first appearance dated in between 500 BC to 300 BC) refers to the traits and the use of crossbows. One of the earliest reliable records of this weapon in warfare is from an ambush, the Battle of Ma-Ling in 341 BC.
By the 200s BC, the crossbow was well developed and quite widely used in China. Several remains of them have been found among the soldiers of the Terracotta Army in the tomb of Emperor Qin Shi Huang (260-210 BC).
Medieval Europe:
The use of crossbows in European warfare dates back to Roman times and is again evident from the battle of Hastings until about 1500 AD. They almost completely superseded hand bows in many European armies in the twelfth century for a number of reasons. Although a longbow had greater range, could achieve comparable accuracy and faster shooting rate than an average crossbow, crossbows could release more kinetic energy and be used effectively after a week of training, while a comparable single-shot skill with a longbow could take years of practice.
Comparison to regular bows:
With a crossbow, archers could release a draw force far in excess of what they could have handled with a bow. Moreover, crossbows could be kept cocked and ready to shoot for some time with little effort, allowing crossbowmen to aim better. The disadvantage is the greater weight and clumsiness compared to a bow, as well as the slower rate of fire and the lower efficiency of the acceleration system.
In the armies of Europe, mounted and unmounted crossbowmen, occupied a central position in battle formations. Usually they engaged the enemy in offensive skirmishes before an assault of mounted knights. Crossbowmen were also valuable in counterattacks to protect their infantry. The rank of commanding officer of the crossbowmen corps was one of the highest positions in any army of this time. Along with polearm weapons made from farming equipment, the crossbow was also a weapon of choice for insurgent peasants such as the Taborites.
Mounted knights armed with lances proved ineffective against formations of pikemen combined with crossbowmen whose weapons could penetrate most knights' armor. The invention of pushlever and ratchet drawing mechanisms enabled the use of crossbows on horseback, leading to the development of new cavalry tactics.
Crossbows were eventually replaced in warfare by gunpowder weapons, although early guns had slower rates of fire and much worse accuracy than contemporary crossbows.
In Western and Central Africa, crossbows served as a scout weapon and for hunting, with enslaved Africans bringing the technology to America. In the American south, the crossbow was used for hunting when firearms or gunpowder were unavailable because of economic hardships or isolation.
Today, Crossbows are mostly used for target shooting in modern archery. Although, in many parts of the world they are still used for hunting, such as parts of North America, parts of Asia, Australia and Africa. Other uses with special projectiles are in whale research to take blubber biopsy samples without harming the whales.
Below are a few definitions of crossbow terminology...
ARROW
Synonym for bolt which is preferred by some modern crossbow manufacturers.
BARREL
Section of the stock between the latch and lath; sometimes used as synonym for track.
BARRELED CROSSBOW
Crossbow having a tubular barrel rather than a track; used to shoot balls, usually of lead; synonym for slurbow.
BENDING LEVER
Hindged lever to aid cocking; pushes string back using lugs or a ring mounted at front of crossbow; provides mechanical advantage of about 5:1, varying with lever length.
BOLT
Short projectile for crossbow resembling arrow.
BOWSTRING
String used on all archery weapons to transfer force from bow to projectile.
CLIP
Spring used to retain bolt to cocked crossbow prior to shooting; usually made of horn or metal.
COCKING
To draw bowstring from braced position to latched position.
CRANEQUIN
Cocking device using rack and pinion; can provide mechanical advantage of about 145:1, varying with size and number of teeth.
CROSSBOW
Archery weapon consisting of a lath mounted to a rigid stock, having a mechanical means to hold and release the drawn bowstring.
DOUBLE STRING
Complex form of bowstring designed to launch round projectiles from crossbow; has leather pouch at center to hold ball.
DRY FIRE
To release cocked bowstring without projectile; term borrowed from firearms.
GOAT'S FOOT
Two-piece hindged cocking lever designed to pull bowstring from behind latch (curved shape of lever vaguely resembles goats leg); provides mechanical advantage of about 5:1, varying with lever length.
LATCH
Mechanism for holding crossbow bowstring in cocked position, and for releasing bowstring when trigger is pulled. Synonym for catch.
LOOSE
To launch an archery missle.
NOCK
Forked protective cap on rear of bolt; usually necessary with trackless crossbows to keep bolt in contact with string. Notches at each end of bow or lath to accept string are also called nocks.
PROD
Bow portion of crossbow.
STIRRUP
Device for holding the crossbow with feet while cocking; usually 'D' or 'T' shaped, sometimes made from webbing or rope.
STOCK
Portion of the crossbow to which all other components are attached and by which it is held.
TRACK
Grooved portion of the crossbow between the lath and latch where the bolt rides.
WINDLASS
Crossbow cocking device using a system of pulleys and cords; provides mechanical of about 45:1 depending on construction.
This article is getting a bit lengthy. So I'll end it here, and pick it back up with part 2. If you're reading this anywhere but on our website, you may need this link to find part 2...
www.naselfdefenseproducts.com/self_defense_information
Just copy and paste the address into your web browser, and when you arrive, click on the link for Articles and stories.
Bye for now,
Steve/NASP
www.naselfdefense.com
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