Tap to Read ➤

Compound Bow Tuning

Medha Godbole Sep 27, 2018
Compound bows facilitate accurate aiming with significant ease due to the presence of the cables and pulleys that allow its limbs to bend. Here are some tips for tuning and maintenance of this instrument.
Modern-day archery is quite different from what it was in the past.
Unlike the olden days where an archer heavily relied on the strength of the arms and hand-eye coordination, the modern-day archers are now using compound bows with levering system, pulleys, and cables that provide the distinctive pull advantage by bending the limbs.
These bows are not affected by temperature changes and humidity, which makes them a good choice. This instrument of archery is very energy efficient. Stringing and tuning of this bow could be a tough job, if the user is not acquainted with it.

Tuning a Compound Bow

Adjust and Optimize

Compound bows provide good output when draw force is at its maximum. Hence, there are a few things you need to check to gauge the basic set up. Checking and correcting these things will also help in enhancing the performance.
For this, keep a bow press and a laser alignment at your disposal. Place the laser alignment on the cam/pulley and align the laser to the idler wheel. After you compress the bow limbs, twist or untwist the cable connected to a side of the idler wheel for aligning it with the cam.
Follow this by removing your bow from the bow press and check with the laser alignment tool. To adjust the cam's height, add or eliminate a few twists in the cable. In case you use a peep sight, make sure that you have it at the correct height. You can make the adjustments in this instrument using tuning tools.

Spine of the Arrow

The spine of the arrow, which refers to the stiffness of the arrow, is an important variable, when it comes to accuracy. If the spine is not correct, the quality of the shaft output is minimal. The arrows need to have the right stiffness to achieve a correct trajectory and to arrive at the point it is aimed at.
You can either do it through a bare shaft panel test or a powder test. When it comes to hunting with a bow, this process is quite important.

Bare Shaft Panel Test

Get hold of 3 fletched arrows along with 3 bare shafts. Fletching is a process of stabilizing the flight of arrows using feathers and such materials. This test has to be an on field exercise. Shooting the arrows with bare shafts, characterized by broad-heads, is unpredictable with dangerous flight patterns.
Remove the fletch (20 to 30 grains, approx.), after masking a few strips of tape to the end of the bare shafts. The tape winding compensates for weight loss by the bow on account of the removal of fletching. The bare shafts should weigh exactly the same as fletched arrows.
Shoot both type of arrows at the target board. If the bare shafts are aligned to the left of the modified shafts on the target surface on impact, make the necessary spine adjustments in the arrow.

Powder Test

A very effective way to eliminate fletching contact prior to tuning is to spray foot powder on the vanes, before you hit the practice range. The problematic areas will be lighted by the powder and you would be able to rectify and adjust the pitfalls.

Broad head Tuning-Arrows

Screwing broad-heads onto the arrows without giving a thought to blade alignment is not advisable. There should not be a mismatch between the broad-head and the vane (thin piece of plastic that is used for making a fletching), as the arrow is released. A longer vane will help in better control over the broad-head.
For controlling a 25 grain broad-head, 4.18 inch vane along with extreme right spiraling is advised.

Broad-head Tuning-Bow

A 3 blade broad-head will identify any slight drawback in the tuning process. The most efficient test is done by shooting 6 fletched arrows at a 20-yard target. After the shoot, step back to 40 yards and see the difference. Set your center shot accurately for preventing your arrows to go awry.

Draw Weight Correction

While you aim your sight pin at the target, in case you need to draw the bow across your chest, you are pulling an excess weight. To correct this, the weight of the bow is adjusted in a way which allows a steady hold on it for a longer period.