whats the highest hook rating can a ball get

A general indication for a ball's hook potential is its RG differential - the higher, the more flare a ball CAN produce through its drilling, and the earlier it can hook. The current legal maximum of new balls is 0.06", some older (but still legal for use, e .g. Visionary's Immortals) equipment can have up tp 0.08", which is a LOT.

A low RG is also helpful, as well as a sanded surface.

BUT: this does not mean that this ball will cover tons of boards on any condition. "Big hookers" tend to need plenty of oil, so the ball's setup will have to match the conditions it is intended for.
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DizzyFugu - Reporting from Germany

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What is the current definition of hook?

The amount of boards covered on the backend?

The amount of boards covered from the ball's farest point right until it hits the pins?

How soon the ball begins making a move?

I've never been impressed with the perfect scale, but I've found the Bowling This Month reviews to be fairly accurrate in terms of comparison among the brands. You can find the updated list here:

http://home.earthlink.net/~litefrozen/index.htm

Remember what hooks the most will vary depending on the bowler, surface and layout of the ball.

For example depending on the shot I'm bowling on my Spitfire will hook more total boards than my Cell on regular house shot, but on longer or sport patterns my Spitfire goes straight while my Cell comes to life. Hook ratings really are just the starting point when making a decision. You can get a good bunch of balls all around the same hook point and then do research through reviews and videos to achieve what your looking for.
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