Tuning/Arrow Build Info

Apps:

Their is a ton of great information available in the new app "Bow Shop Bible".  Make sure to check it out here - https://bowshopbible.com  If I am trying to assist you with tuning over the phone this app will make a great reference tool.

Tuning:

*Tuned is tuned.  Period.*

 Key Points:

  • Bow should be set to all factory specs: Axle to axle, brace height, timing, sync, cam lean, etc.
  • Rest should be centered (majority of bows 13/16th of an inch)
  • Rest and Nocking point should be level with arrow running through the Berger hole
  • Left/Right tears are primarily indicating a misalignment of the rest and the strings path during its power stroke.  The goal is for the rest to stay within 1/16th of true center.  To accomplish this mass adjustments should be made via yoke adjustments or shimming to adjust cam lean and thus correct the string position.  In the majority of cases these mass adjustments will be done in the first 10-15 yards of bare shaft tuning.  Beyond this point mass adjustment will likely be too large and at that point you will fine tune using the rest.
    • When a misalignment is present, the side of the shaft will push against the rest.  This pressure will cause the tail to rebound and kick away from the side experiencing the pressure.
    • Spine changes can alleviate this as the amount of flex will alter the amount of pressure created, but this is not the preferred method as it means you are forcing the shaft to flex more than desired which is inefficient and can lead to other flight issues from being underspined
  • Up/Down tears are indicating that nock travel is present.  This could be from the cam sync, timing, tiller, nocking point, etc.  I prefer to tune with a known stiff shaft in order to be able to see the nock travel easier and correct it.
    • If timing, sync, tiller, arrow level, etc all look correct but a vertical tear still exists then likely the nocking point is slightly off of "center".  Move the rest & nocking point up/down together to maintain arrow level to correct.
    • If a nock high exists after checking all of this then the shaft may be reacting weak.  Reduce point weight or draw weight to confirm if the tear improves.
      • Nock high can be a weak reaction as the shaft will flex the path of least resistance (up) causing the point and nock to be down during launch.  The mass at the front of the shaft resists the shaft straightening and causes the tail to raise as the shaft straightens out.  

Arrow flight quality is a critical piece of your accuracy with broadheads (they should hit with your fieldpoints) and is a major factor in your penetration.  Do everything you possibly can to achieve perfect arrow flight!

General Corrections:

The following are general fine tuning suggestions.  This is assuming that the bow is in factory specifications, timing/sync are verified correct, cam lean is properly set, arrow is level and in line with the center of the berger hole, and rest is centered (typically 13/16").  Any issues with these initial steps can create larger issues that cannot be properly resolved with these fine tuning suggestions.

  • Nock Left = Broadhead Impact Right
    • Correction: Move Rest To The Right
  • Nock Right = Broadhead Impact Left
    • Correction: Move Rest To The Left
  • Nock Low = Broadhead Impact High
    • Correction: Move Rest & Nocking Point Down.  Arrow Should Stay Level
  • Nock High = Broadhead Impact Low
    • Correction: Move Rest & Nocking Point Up.  Arrow Should Stay Level

If more than 1/16" movement is needed for any of these corrections there is likely a larger underlying issue that should be addressed. 

Left/Right issues can be caused from incorrect cam lean, grip issues, facial pressure, ect. 

Up/Down issues can be caused from incorrect timing/sync, grip/form issues, limb bolt positions, etc.  Any contact occurring with the arrow can cause a variety of issues. 

Make 1 adjustment at a time and confirm the results match your expectations before proceeding.