Recurve bow

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Modern recurve bow
Modern recurve bow

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[edit] Definition and characteristics

A recurve bow is a form of bow defined by the side-view profile; in contrast to the simple longbow, a recurve bow has tips that curve away from the archer when the bow is aimed. The technical difference between recurve and other bows is that the string touches sections of the limbs of recurve bows when strung, while only having contact with the tips of other bow types. A recurve bow stores more energy than an equivalent straight-limbed bow, giving a greater amount of cast to the arrow. A recurve will permit a shorter bow than the simple bow for a given arrow energy and this form was preferred by archers in environments where long weapons could be cumbersome, such as in brush and forest terrain, or while on horseback. The recurved limbs allow for:

  1. A lower bracing height with the same limb length, or a shorter limb length with the same bracing height,
  2. More spring force over the first few inches of draw, and
  3. A smoother draw.

By contrast, the traditional straight longbow tends to "stack"—that is, the required draw force increases more rapidly per unit of draw length as the string is drawn back.

Recurved limbs also put greater strain on the materials used to make the bow, and they may make more noise with the shot. An unstrung recurve bow can have a confusing shape and many Native American weapons were incorrectly strung backwards and destroyed when attempts were made to shoot them. This is especially true of the reflex bow. Like the recurve bow, this design is used to increase the amount of stored energy in the bow. However, the reflex bow when unstrung flexes its entire self away from the archer, like a backwards "C". When strung it resembles a strung recurve bow.


[edit] Historical use

Composite bows with recurve were used by, among other groups, the Hyksos, Magyars, Huns, and Mongols. The recurve bow spread to Egypt, much of the rest of Asia, and the Middle East countries in the second millennium BC. Presumably Greek and Phoenician influence would have introduced the recurve form to the rest of the Mediterranean region. The standard weapon of Roman imperial archers was a composite recurve, and the stiffening laths used to form the actual recurved ends have been found on Roman sites throughout the Empire, as far north as Bearsden in Scotland. During the Middle Ages composite recurve bows were used in the drier European countries; the all-wooden straight longbow was the normal form in wetter areas. Recurved bows depicted in the British Isles (see illustrations in "The Great War Bow") may have been composite weapons, or wooden bows with ends recurved by heat and force, or simply artistic licence. Many North American bows were recurved, especially West Coast bows. Recurve bows went out of widespread use with the availability of effective firearms.

[edit] The modern recurve bow

The recurved form is employed in traditional weapons, composite bows or wooden, and in high-technology competitive bows. A typical modern "recurve bow", as used by archers in the Olympics and many other competitive events, will employ advanced technologies and materials. The limbs are normally made from multiple layers of fiberglass, carbon and/or wood on a core of carbon foam or wood. The riser (the handle section of the bow) is usually separate and is constructed from wood, aluminium alloy or magnesium alloy. A range of aluminium/carbon hybrid bows have emerged of late and an Italian manufacturer has begun to produce a carbon fiber riser. Risers for beginners are usually made of wood or plastic. The high-technology materials allow predictable manufacture for consistent high performance, and the easy attachment of modern aids to accuracy.


The modern recurve is the only form of bow permitted in the Olympics (though the Compound bow is permitted in some categories at the Paralympic Games) and is the most widely used by European and Asian sporting archers.

The modern Olympic-style recurve is a development of the American Flat Bow, with rectangular-section limbs that taper towards the limb tips. Most recurves today are "take-down" bows—that is, the limbs can be detached from the riser for ease of transportation and storage, and for interchangeability of limbs. Older recurves and some modern hunting recurves are one-piece bows. Hunters often prefer one-piece bows over take-down bows because the limb pockets on take-down bows can often be a source of noise.

[edit] Parts of a Recurve Bow

These are the standard parts of a modern recurve bow:

  • Arrow rest - Where the arrow rests during draw. These may be simple fixed rests or may be spring-loaded or magnetic flip rests.
  • Back (of bow) - The face of the bow on the opposite side to the string
  • Belly (of bow) - The face of the bow on the same side as the string
  • Bow sight - Used on all recurves, except those of archers shooting Barebow. Helps the archer aim in the same place each time.
  • Sling - A strap attached to the bow handle, wrist or fingers to stop the bow falling from the hand
  • Bracing height - The distance between the deepest part of the grip and the string
  • Grip - The part of the bow held by the bow hand
  • Limbs - The upper and lower working parts of the bow, which come in a variety of different poundages
  • Nocking point - The place on the bowstring where the nock (end) of an arrow is fitted
  • Riser - The rigid centre section of a bow to which the limbs are attached
  • String - The cord that attaches to both limb tips and transforms stored energy from the limbs into kinetic energy in the arrow
  • Tab - A protection for the fingers that draw the string. Usually made in leather.
  • Tiller - The difference between the limb-string distances measured where the limbs are attached to the riser: usually the upper distance is slightly more than the bottom one, resulting in a positive tiller. Reflects the power-balance between both limbs.

[edit] String Material

The following types of string material are commonly used with a recurve bow.

Dacron B50 - (strength per strand = 22.5 kg. , stretch = 2.6%) is a polyester material. Because of its durability and stretch, Dacron is commonly used on beginners equipment and older bows. The relatively high stretch causes less shock to the bow, which is an important consideration for wooden-handled recurves. Dacron strings are easy to maintain and can last several years.

Kevlar 7-11 - (strength per strand = 31.8 kg. , stretch = 0.8%), also known as aramid, is a liquid crystal polymer material with a higher density and smaller diameter than Dacron which results in a faster arrow speed. (approx. 2 metres per second). There are two problems with this material. Firstly, its limited stretch causes increased stress in the bow limbs. Check with the bow manufacturer whether a Kevlar bowstring can be used. Secondly, a Kevlar bowstring may only last 1000 shots before breaking as it tends to fatigue due to bending at the nocking point. Failure tends to be sudden rather than gradual.

Fastflight - (strength per strand = 45.5 kg. , stretch = 1.0%), introduced in the 1990s, is a high modulus polyethylene material, also known as Spectra. It has largely displaced liquid crystal polymers like Kevlar for bowstrings as it is more durable and fails more gradually. As the material has less stretch than Dacron, it is advisable to check with the bow manufacturer whether it can be used. Fastflight is made from a polyethylene derivative giving it a 'plastic' look and feel. It is very slippery, so the servings have to be wrapped very tight otherwise they will slide. Special serving material has been developed to help overcome this problem. In 2006, all US-based Spectra production facilities were requisitioned by the US Government, since Spectra is also used in body armour. Production of Spectra-based Fastflight has thus ceased, but the manufacturer (Brownell) has launched several alternatives, such as the Dyneema-based Fastflight Plus.

Fastflight S4 - (strength per strand = 73 kg. , stretch = less than 1.0%) is made from a composite of 50% Fastflight and 50% Vectran making the strands thicker. Therefore approx. half the number of strands are required as for a Fastflight string. Vectran is a liquid crystal polymer similar to Kevlar. Mixing it with Fastflight avoids many of the durability problems associated with liquid crystal polymers.

Dyneema is a high modulus polyethylene material. It has very similar characteristics to Fastflight, though with a little more stretch. For this reason, many recurve shooters prefer Dyneema and find it more "forgiving" than Fastflight. With Fastflight becoming commercially scarce, most recurve archers are switching to Dyneema.

Linen and other traditional materials would be very unusual on a modern recurve bow, but are still effective and still used on traditional wooden or composite bows.

[edit] Other Equipment

Recurve archers often have many other pieces of equipment attached to their recurve bows, such as:

  • Clicker - a blade or wire device fitted to the riser, positioned to drop off the arrow when the archer has reached optimum draw length. Used correctly, this ensures the same cast-force each time. Many archers train themselves to shoot automatically when the clicker drops off the arrow.
  • Kisser - a button or nodule attached to the bowstring. The archer touches the kisser to the same spot on the face each time (usually the mouth) to give a consistent vertical reference.
  • Plunger Button - a fine-tuning device consisting of a spring-cushioned tip inside a housing. The plunger button screws through the riser so that the tip emerges above the rest. The side of the arrow is in contact with the tip when the arrow is on the rest. The spring is tuned so that it allows a certain amount of movement of the arrow towards the riser on release, bringing the arrow to the ideal "centre shot" location. The plunger button provides some degree of "forgiveness" of bad releases, since it removes some of the resulting excess sideways energy. The device is also known as a pressure button or Berger button (after its inventor, Vic Berger).
  • Stabilisers - weight-bearing rods attached to a recurve bow to balance the bow to the archer's liking, dampen the effect of torque and absorb some vibration.


[edit] See also

[edit] Bow construction techniques

[edit] Other bow forms


[edit] References


Coulston JC. 'Roman Archery Equipment', in M.C. Bishop (ed.), The Production and Distribution of Roman Military Equipment. Proceedings of the Second Roman Military Equipment Seminar, BAR International Series 275, Oxford, 1985, 220-366.

The Great War Bow. Hardy R, Strickland M. Sutton Publishing 2005. ISBN-10: 0750931671 ISBN-13: 978-0750931670

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