Pro Shop Operator’s Guide To
AMF Ball Drilling Techniques
This drilling produces a good skid through the front part of the lane, with
an even arcing backend reaction.
Place pin at 1:30 in relation to CG. Place CG at center of grip.
Use Pin Medium.
Simplified Drilling Techniques
For use without determining the bowler’s Positive Axis Point.
The following drillings are for those times when a PAP is not available. These drillings give the bowler three different
amounts of hook,with three distinctly different break points. Please note, to avoid tracking over the finger holes, keep the
pin lined up with or slightly above the finger holes.
Key to drilling diagrams:
= Pin (top of weightblock)
= Balance Hole
= Center of Gravity (CG)
= Centerline of Grip
Pin In = 0-2” from CG; Pin Medium = 2-4” from CG;
Pin Out = 4-51/2” from CG
This drilling is excellent when playing inside angles. It produces good
skid through the front part of the lane, with a defined break point and a
strong forward roll into the pins.
Place pin over ring finger at 10:30 in relation to CG. Place CG on mid-
line 2” from center of grip. Place balance hole 41/2” from center of grip
Use Pin Medium or Pin Out.
LENGTH/FORWARD ROLL DRILLING
This drilling will produce the most hook and strongest backend reaction.
This technique works well from any angle when trying to create area on
Place pin at 12:00 in relation to CG. Place CG on midline 2” from
center of grip. Place balance hole 41/2” from center of grip on midline.
Use Pin Medium.
MAXIMUM HOOK AND BACKEND DRILLING
1.When determining the PAP on a large flare potential ball, subtract 3/4” from bowler’s
horizontal axis coordinate when axis point is measured on a ball with 1“ or less of flare.
If the axis point is measured on a ball with 1” to 3” of flare, subtract 3/8” from bowler’s
horizontal axis coordinate to determine th