I watch a lot of baseball. I can't seem to help myself, I watch my NY Mets blow games on a regular basis. One thing sticks out and puzzles me, bullet spin. The slider is a big part of a baseball pitcher's arsenal and it is basically bullet spin. The slider breaks late, down and away to a pitcher's glove side. How does bullet spin break? I did some research and found an explanation that explains the break and why it occurs 'late'.
Everyone knows what bullet spin is: the spin axis is horizontal and pointed in the direction that the ball travels, the magnus force is distributed evenly around the ball thus there is no break. However as the ball slows down it's trajectory changes significantly in a downward direction, yet the spin axis remains horizontal. As the ball 'sinks' the air flow changes, there is more contact with the 'bottom' of the ball and this generates enough magnus force to cause the ball to break. Imagine throwing a football where the spin axis remains horizontal for the whole distance, as the ball loses speed and starts to fall it will drift to the left (for a right hander).
How does this apply to softball? If you want a curveball with a lot of late break don't throw it with perfect horizontal spin, you need to tip the axis up a little so that as it loses speed the spin will line up with the change in air flow and there will be more magnus force. Half bullet, half curve, or something close to that should do it.
Everyone knows what bullet spin is: the spin axis is horizontal and pointed in the direction that the ball travels, the magnus force is distributed evenly around the ball thus there is no break. However as the ball slows down it's trajectory changes significantly in a downward direction, yet the spin axis remains horizontal. As the ball 'sinks' the air flow changes, there is more contact with the 'bottom' of the ball and this generates enough magnus force to cause the ball to break. Imagine throwing a football where the spin axis remains horizontal for the whole distance, as the ball loses speed and starts to fall it will drift to the left (for a right hander).
How does this apply to softball? If you want a curveball with a lot of late break don't throw it with perfect horizontal spin, you need to tip the axis up a little so that as it loses speed the spin will line up with the change in air flow and there will be more magnus force. Half bullet, half curve, or something close to that should do it.
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