Oil length is really subjective - additionally, there is also an effect through the amount of oil and the friction by the lane surface material.
I play on a 40' sport pattern, and it is medium oil from what I know. But the lane surface is so slick, even the heaviest particle balls only work slightly!
On the other hand I have another house nearby whre they apply a 30' light oil pattern, where the backend friction is so dry that even mild reactives are hard to keep away from Brooklyn!
I'd consider 50' of oil to be a long pattern, and anything less than 35' to be short - but this is a personal view. Dunno if there a´re official definitions, i. e. by the PBA?
PS:
Just an addition to the topic - Storm had in the 2003 catalogue a nice matrix for their balls with oil amount and pattern length. I found this very comprehensive, wondering why they dropped this concept?
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DizzyFugu --- Reporting from Germany
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