10's are about entry angle and retaining energy at the pins. The clue as to what is going on is watching the ball go through the pins and where the ball falls off the end of the pin deck. Below is based on being right handed. And this is old school knowledge that still works today. Of course todays ball's have much more power and bowlers today have much more speed, but I believe the information below is still valid (at least for me). As well, you must also determine topical issues such as off spot pins, bad pins and lane surface (such as levelness). Sometime topical issues can not be overcome by specific players while others it helps.

The goal to great carry is to have to ball not deflect right or left but travel straight through the pins on the same trajectory as the entry angle toward the pins.  The ball should hit the pocket on ~17.5 and fall off of the pin deck at ~18. If the ball deflects right (an falls off the pin deck ~16.5) you will typically leave a flat 10. If the ball goes left you stand to leave an 8 or 9 and even a 4.

Now for ringing 10's where the ball appears to go straight through the pins it is about entry angle. Somewhere between ~4/5 degree entry angle's will result in ringing 10's on a consistant basis. So you must either increase the entry angle or decrease the entry angle to change the ringing 10. This is usually done by moving your target several boards left of right (and your feet appropriately where moving left will create more entry angle and moving right will lessen entry angle).


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