The Importance of Knowing the Anatomy of Your Hunting Arrows
Knowing your equipment is the first step in trusting that you can get the job done, no matter what that particular “job” is. Nowhere is this statement more correct than when it comes to hunting equipment designed to take an animals life. However, the common misconception is that the bow is the object doing the killing. It’s not…it’s the arrow, the object that delivers the final blow. So an ethical question is this…”do you know the anatomy and important features of your hunting arrows?”
There are five basic parts that make up your hunting arrows: the point, the insert, the shaft, the nock, and the fletching. Hunting arrows have these five things in common, but that is the only similar features among arrows. Every arrow is going to have a specific weight, spine tolerance, and length that is important to the optimal use of an arrow with a particular bow’s specification as well as the game the hunter is pursuing. Ethical bow hunting is knowing what you are slinging towards another living thing, and being confident that this object is set up for the most effective, quick, and painless death it can deliver.
There are a variety of points that can tip an arrow: field points, broadheads, judo-points, or blunt-tips. Field points are available with longer tips or more blunt tips. Broadheads can be fixed or expandable blade. There are broadheads customized for specific game animals such as small game or turkey with a variety of tips and cutting diameter. These points are available in a variation of styles made of a variety of materials. The point, regardless of style, is weighed in grains and commonly available in 75, 100, 125, and 150 grain. You should always practice and sight your bow in the same grain weight of the broadhead that will be used for hunting.
Inserts are aluminum, brass, or plastic sleeves which is slightly smaller than the diameter of the shaft and has a slightly larger rim to keep it from going completely into the arrow shaft. The insert is placed into point end of the arrow shaft and glued in. The insert provides a threaded end to insert and screw on points.
Some brass inserts, having a little more weight than plastic or aluminum, can assist in adding front of center weight for weight forward accuracy and penetration.
Lock-n-Load® Inserts make the job of installing inserts quick and easy! Now within seconds, you can install, index and lock your inserts in place without glue.
Precision, self-centering design improves concentricity by aligning to the center of the shaft resulting in better overall flight accuracy and arrow to arrow consistency. Easily index your blades to your vanes before locking the insert into place.
The shaft is literally the backbone of the arrow and consists of two important components; weight and spine deflection or tolerance. The most commonly used arrows for hunting these days is carbon or a carbon-aluminum blend shaft. Some aluminum arrows are still being shot but are few and far between. Wood arrows are used by primitive-style archers but will not be covered in this writing.
Aluminum shafts are durable and more affordable than carbon. Carbon shafts are a little more expensive but are favored for the lightweight design that comes in a variety of diameters. However, carbon shafts can be damaged easier than aluminum shafts. Aluminum-Carbon blend shafts incorporate an aluminum tube and a carbon outer layer or just the opposite, a carbon tube with an aluminum outer layer. For all practical purposes, the carbon and carbon blend arrow will be within this article.
Arrow weight is more critical than most archers realize when it comes to optimal shooting performance. Ultra-lightweight arrows, such as those used by competition archers, will typically travel in a straighter line and group more tightly. There are lightweight hunting arrows designed for hunting that have similar characteristics. Heavier arrows will deliver more kinetic energy for better hide and flesh penetration on game animals while still retaining a good grouping.
The arrow weight for hunting is recommended of a total weight of 6 to 8 grain per pound of draw weight. It is important to never use an arrow with less than 5 grain per pound of draw weight with any bow; doing so could cause damage to the bow and injury to the archer similar to that of dry-firing a bow
Every arrow is going to have a certain stiffness referred to as the spine deflection or spine tolerance of the shaft. Arrow weight and arrow spine deflection are often confused as being the same thing; they are not. The spine deflection is technically the most important trait of an arrow but probably the most misunderstood characteristic of an arrow. This misunderstanding is often a result of different manufacturers using different spine numbers for each shaft tolerance; there is no standard as to labeling. There is, however, a standard to measuring the spine tolerance.
Ultimately, it is important to make certain that you purchase arrows that have a spine tolerance for the draw weight of the bow being used. Often the arrow manufacturer will advertise that an arrow is “suitable for bows up to a 70-pound draw weight” or “suitable for bows up to a 50-pound draw weight.”
Arrow length is also critical to optimal shooting. Typically, a bow hunter will want the arrow shaft to extend out at least two inches from the rest contact at full draw. This measurement can be affected by the type of rest that is on the bow. It is important that the broadhead has proper clearance from the bow and the archer’s hand/fingers.
The three vanes on arrows are known as fletching and can be made up of feathers or pliable plastic material of varying length and height. To allow optimal arrow flight, the fletching can be tuned to the arrow shaft by weight. The three vanes have a cock feather, or index feather, of different color which is used to indicate how the arrow is loaded onto the bow string to allow arrow rest clearance.
Feather fletching is still popular with many archers, but they are not as durable as plastic vanes especially during wet weather or storing. Plastic vanes adhere easier to the arrow shafts, offer more durability, and a more consistent flight. Target archers typically use smaller vanes for less drag, but a small vane will not offer stability with a broadhead. Longer vanes, or shorter, high profile vanes will offer better control for broadheads. Remember, the taller the vane, the more drag the arrow will have in flight.
For the most accurate and consistent flight among arrows, weight tuning is recommended. The easiest way to weight tune a shaft without a professional tuning device is to place a single shaft in a tub filled about a one-quarter full of water that has some soap suds. Place the shaft in the tub and let it spin until it comes to a halt. Roll it once more, making sure the ends are not touching the sides of the tub. Make a mark on the arrow shaft close to the nock on the side facing up. This is the lightest side of the shaft. The cock feather needs to be affixed to the opposite side of that mark; on the heavy side of the shaft. Doing this for all of the arrows will help in the consistency of the arrow groupings.
Fletching is normally affixed to arrows with a two or three-degree helical offset in the vane. Helical offsets have been proven to offer a more stable, tighter pattern with both field points and broadheads. If a bow hunter wants to make certain that the arrow and broadhead are tuned, they can take a fletch tuned arrow, place the insert in the end of the shaft with epoxy cement, screw on a broadhead and match the blades to the vanes.
If a bow hunter walks into a big box store and grabs a handful of pre-fletched arrows, they will find the arrows will shoot down range and hit the mark on the target. More often than not, one or two arrows will shoot consistent every shot. Often, those few are the arrows that are the closest to being tuned. There is nothing wrong with this method of purchasing arrows preseason. For optimal shooting, imagine the advantage a bow hunter would have when they have taken the time to make sure that the arrows are properly tuned, not only for the draw length and draw weight of the bow, but also that the vanes are tuned to shaft weight. Not only would this allow for consistently accurate shooting, but it also goes a long way in building the confidence of the bow hunter.
The nock of the arrow is available in several designs and can easily be removed and replaced. It is important to use the correct nock for the diameter arrow and the right tension on the bow string to prevent it from falling from the bow string when being drawn. A nock that is too tight or too loose can affect the accuracy of an arrow.
The proper fit of the nock will result in a click of the bow string but still allow the nock to turn freely on the serving; not allowing the arrow to torque the bow string when the string is pulled back to full draw. If the nock is too tight, it can result in a late release of the nock from the string, causing the string to pull forward resulting in an erratic arrow flight. Or, if the nock is too loose, it can cause inconsistent arrow flight or can result in the arrow falling off prematurely.
The press-fit nock is the most common nock used on arrows. The design allows the nock to be easily turned so that it can be positioned in alignment with the fletching to clear cables and rests. Nocks are available in diameters to fit snugly in the shaft. These diameters range in increments from .166-inch to .246-inch in diameter and are marketed in common sizes of G, F, X, A, H, S and GT. A bushing can be added to ensure that the nock will not damage the arrow shaft.
Another popular nock among bow hunters is the lighted nock. This nock incorporates a lighted end when it is shot from a bow, allowing the hunter to have a visual representation of the shot and assists hunters in being able to retrieve the arrow for inspection on a pass through, or for finding downed game in the dark. Using a lighted nock during practice can also assist the archer in seeing the arrow’s flight to the target.
A lighted nock is not going to significantly affect the grouping of arrows for the fact that a press-fit nock weighs 11-16 grains depending on brand; whereas a lighted nock such as Nock-Out Lighted Nocks weighs 21-24 grains. There is an insignificant difference in the amount of weight of 10 to 13 grains depending on the brand of nock that the lighted nock is replacing. The minimal length added of half an inch and the insignificant amount of added weight to the nock end of the arrow results in most archers not experiencing much change in the accuracy of their groupings and tuning of the sight is often unnecessary for optimal shooting.
Nock Out Lighted nocks feature a practice mode. This mode allows a hunter to shoot the nocks without having to waste the battery life. This allows the bow hunter to ensure his/her hunting arrows are hitting their mark with the lighted nocks attached.
Knowing the anatomy of your hunting arrows will provide you a foundation to build from. This will inevitably lead to a more accurate arrow build, tighter groups, and an effective arrow that can punch through the game it is designed for.