C.O.R., or better known as coefficient of restitution, is the amount of energy returned to the pin as the ball contacts it.
In basic physics, it is known that for every action there is an equal and opposite reaction. C.O.R. is just the number that tells us how much of the energy of impact is returned to the pin upon contact. The higher the number, theoretically, the higher the pin action due to the impartation of a higher percentage of energy returned.
And as far as cover all the way down to the core, faball ( and I'm sure they weren't the only ones ) ) used to do this with all the old urethane hammers back in the day. Many ball makers soon followed suit.
Now, ebonite has done a study of this very subject and has come to the conclusion ( or so the article I read said ), that thin coverstocks over a larger inner core lets the ball have a more consistent reaction and more carry properties due to improved angle of entry.
I don't remember where I read the article, it was in a magazine down at the bowling center. I will look next time I'm there and see if I can find it. If so, I will post what magazine it was in.
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Beware the JUGGERNAUT!
"The difference between stupidity and genius is that genius has its limits."
Albert Einstein
