The arrow is one of the most often overlooked parts of the bow and arrow technology. A common trope in literature and film is that archers can simply pick up the arrows shot at them from different bows and shoot them back. But this would be like trying to shoot a bullet made for a .30-.30 rifle out of .22 rifle. The bullet won’t fit because the .30-.30 bullet is too large for the .22. It wasn’t constructed for that weapon. Likewise, an arrow that performs well out of a 30 lbs. bow will shatter if it is shot out of a 120 lbs. bow. An arrow that performs well with a 120 lbs. bow, won’t fly far at all when shot from a 30 lbs. bow. There are two reasons for this—spine and weight.

The spine of the arrow describes how stiff it is. Stiffness matters because, prior to modern center-shot bows (which means what it sounds like), arrows had to flex around the bow handle when the string was released and the energy stored in the limbs was transferred to the arrow. Because an object at rest will resist acceleration, the front of the arrow with the tip that is heavier than the back of the arrow, will resist motion. The shaft has to flex to accommodate this resistance. This flexing of the arrow around the bow is called the “archer’s paradox.” If you want to see this, just do a quick Google search for it. The film Brave has a great example of the archer’s paradox. The problem is that the arrow has to be limber enough to bend around the handle and then correct itself without breaking.

Archer’s Paradox

Weight also matters because a heavier arrow will absorb more energy as it flies. Consequently, it will not travel as far or with as much speed as a lighter arrow. But a heavier arrow will penetrate more effectively than a lighter arrow. Still, there are ways to get the best of both worlds. English war arrows, for example, were often barrel-shaped in that they tapered from the middle toward each end. The famous archery historian, Hugh Soar, argues that “barreling a shaft reduces vibration during initial flight, thus improving distance made.”^[1]

All of this matters because, when it comes to accuracy, having the arrow properly matched to the bow is far more important than the style of bow being used. Prior to modern manufacturing, it was impossible to build arrows that were exactly the same spine, weight, and FOC, which meant each arrow would fly differently. When an archer states that his bow shoots where he is looking, it isn’t the bow. It’s the arrow. In that case, the arrow is perfectly matched to the bow and the archer.

Anciently, arrows were made from reed, or cane, and wood—sometimes both. It is common to find historic arrows around the world in which the back of the arrow is made from cane and the front is made from a wooden foreshaft. Prior to our modern ability to measure arrow weight and stiffness with precision, it was impossible to get a dozen arrows that were evenly matched. Saxton Pope commented on this when he observed that Ishi, the last Yahi Indian, was being inconsistent in his shooting. The problem wasn’t his skill. It was that his arrows were not matched in weight and so each flew slightly differently.^[2] This means that the kind of superhuman accuracy attributed to some ancient archers, such as the mythological Robin Hood, should be taken with a pound of salt. Their superhuman accuracy was relative to the accuracy potential of the tools they had.

Wooden arrows also have a tendency to want to return to the original shape of the branch or tree from which they came. Consequently, archers who used, or still use, wooden arrows have to spend time straightening their shafts before shooting.^[3] This is done by heating the wood and applying pressure to the bent arrow. A lot of energy had to go into straightening arrows because, quite simply, a bent arrow won’t fly straight. Plains warriors in what is now the United States cut grooves in the arrow shaft because they believed it prevented the arrow from warping.^[4]

The long and short of all of this is that an arrow must be matched to the draw weight of the bow in spine and weight to get the most efficient flight. An archer on a battlefield who doesn’t need accuracy and can assume the arrows were mass-produced for specific weight bows that were also mass-produced might get away with snatching up an arrow and shooting it back. But if the match isn’t pretty close, he might regret it when the arrow breaks and fills his hand with splinters.

^[1]. Soar, Straight and True, 100.

^[2]. Pope, “Yahi Archery,” 123-126.

^[3]. See Cosgrove, “Wooden Arrows,” 227-244.

^[4]. Red Hawk, “Lakota Sioux,” 112.