Determining the appropriate arrow spine and length for your traditional bow is a little like shopping for new clothes:  one size definitely does not fit all! In fact, just as it is true that a size 10 in one designer’s clothing line is not the same size 10 made by another designer, tuning arrows to a bow is no different.  Just because two traditional bows may be of equal weight at the same draw length, if they are made by different bowyers, odds are the perfect arrow for each bow may be different.  However, through the use of the bareshaft tuning method, every bow can find the perfect arrow match.

Bareshaft tuning is an important step in finding the perfect arrow for a given bow.  It enables an archer to observe arrow flight, set the proper nock point, and create an arrow that will fly perfectly when fletched.  I use this method for every new bow I buy and highly recommend it to others.

The laws of physics play an important role in arrow balance, behavior, and trajectory.  Without embarking upon a qualitative study of why this is true, suffice it to say that an arrow’s length, point weight, rear weight, and drag from fletchings influence its spine relative to the bow’s design.  Thus, all of these factors must be taken into consideration when preparing to find the perfect arrow for any given bow.  There will be more about this later.  For now, let’s focus on a discussion of the bareshaft method.

To begin, you will need a means of cutting your arrows.  If you shoot carbons, you will need a high speed saw.  Aluminum arrows can be cut using a tube cutter from a hardware store.  Another alternative is to conduct bareshaft tuning at your local pro shop and ask them to do the cutting for you.

First, there are a few basic arrow tuning rules that are of important note.  They are as follows:

• Adding arrow length weakens arrow spine.
• Adding point weight weakens arrow spine.
• Shortening arrow length stiffens arrow spine.
• Reducing point weight stiffens arrow spine.
• Adding rear weight stiffens arrow spine.
• Adding fletchings stiffens arrow spine.
• If an arrow hits consistently to the left (for a right-handed shooter) of the intended target point, it is too stiff.  This would be right for a lefty.
• If an arrow hits consistently to the right (for a right-handed shooter) of the intended target point, it is too weak.  This would be left for a lefty.
• In general, an arrow that is SLIGHTLY weak will be more forgiving than an arrow that is too stiff.

To illustrate this method it is best to begin with an example. So, let’s assume that you have a new traditional bow that is 45# at your 26 inch draw length.  You have decided to shoot Vapor 2000 carbon arrows which are said by the manufacturer to be spined at 35# to 45#.  Remember that all spine testing is done with a 28 inch arrow, so based on the rules above, since your draw is less that 28”, you will likely need to add length beyond 28 inches, add point weight, or both in order to achieve a properly spined arrow for your bow.

The first step in bareshaft tuning is to begin with a full length shaft with a target point installed.  With a carbon arrow, I recommend 175-225 grains of point weight for bows below 50 lbs.  For aluminum or wood, 125 to 150 grains up front should be plenty.  Stand 15 yards from your target with your bow held vertically, aim at the bullseye, draw, anchor, and release.

Since the first thing that must be adjusted is the bow’s nock point, only observe the up and down position of the arrow’s nock in relation to center at this time.  Disregard any left or right movement.

Start with a nock point on your bow string at 5/8” above center and work your way down.  If the arrows are entering the target with a nock low position rather than straight, raise your nock point slightly.  Likewise, if the nock position of the arrow is consistently above center, lower the nock point on the bow slightly.  Repeat this process until your bareshafts are entering your target straight.  Once this is accomplished, it is time to move on to establishing the best spined arrow for your bow.

Shoot your full length bareshaft into a target as above.  Assuming that the arrow is too weak, and you are a right-handed shooter, the arrows will be far right of your intended mark. Cut off ½” of the arrow’s length from the nock end, reinstall the nock, and repeat.  Continue this process until the arrow consistently hits the target 4 to 5 inches weak.  The reason a weak bareshaft is desired is because the weight and drag added to the rear of the arrow when fletchings are applied actually stiffen the shaft.  The result is that a bareshaft that hits slightly weak will hit right in the bullseye when fletched.

Once bareshaft tuning has been completed, a shaft must be fletched and tested.  If your bareshaft testing has been properly done, you should find that your arrows are accurate and incredibly forgiving, which makes them perfect for both target and hunting applications.  Just remember, the set of arrows you have just tuned to a bow may not be appropriately tuned for another bow of similar weight.  As mentioned in an earlier paragraph about arrow tuning and physics, the arrow’s performance is relative to a bow’s design.  Thus, any minor design difference from one bow to another (ie. Centershot) can profoundly influence the best arrow and point weight combination for a given bow.  Therefore, it is prudent to bareshaft a set of arrows to each individual bow.

There is no doubt that the bareshaft tuning method takes both time and effort.  However, in hunting the stakes are high, and when you make a clean kill on the animal of your dreams, I’m sure you will agree that the investment was worth it.

© June 2006