What happens is with the lower grit (320) etc, the rougher the surface, the quicker the ball will roll. You will see a reduction in backend, but with the ball rolling sooner, it will help the ball get up to the pocket quicker for you. The rougher the surface, the sooner the ball rolls because it is creating more friction, helping it grab. Thus the reason why polished bowling balls glide through the heads easier, the ball can not create as much friction between itself and the lane, so it goes further down the lane before making a move. On the other side of this, if you sand it down too much, the ball will only be able to be used on the oiliest of lanes. Any dry the ball encounters will make it want to roll and will probably roll too soon and cause the ball to roll out, hitting like a pumpkin. Thus the reason why you should start at the higher grit and work down to where you like the reaction you get.
Hope this helps!
Clint
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Clint Daley-Owner
Lets Go Bowling Daley
Salem, Ohio 44460
TRACK ADVISORY PRO SHOP STAFF