Centering the Crossbow String's Center Serving Area
The crossbow string’s center serving area should be centered on either side of the latch system for consistent shooting when the crossbow is in the cocked position.
For ease of centering, you may want to use a permanent marker to color the part of the serving on the string that is immediately outside the rail on both sides of the stock when the crossbow is uncocked.
When the crossbow is cocked, you can glance down quickly and check to see if the string is centered.
If the string is not centered, it can be adjusted in the latch by pulling back on the string and moving it until the marks are centered.
A sudden shift of arrow groups to one side is a good indicator that the crossbow is being cocked with the string off-center.
Using a cocking aid–a harness or crank–will help ensure center cocking each time.
For consistent arrow grouping, it is important that the serving is always centered.