Momentum is mass x speed..
so 16 lbs at 20 mph = 12 lbs at 26.6 mph..
unfortunately, the reaction you get on the lanes is dependent upon speed of the ball regardless of the weight of the ball.
at 26.6 mph you are more than likely not going to get the reaction and angle you need to carry.. unless you have a ton of revs..
If you throw the ball straight at the pocket like a rocket then throwing it harder will help it hit like a 16 pounder..but then throwing harder usually reduces accuracy for most people..
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16-17 mph,350 rpm,PAP 5 1/2 x 3/8up, HighGame 300 x 4, High Series 808
Book Average 205,PBA Xperience ave180