Do thier covers have an MB marked on them?
If so, what is the mass bias differential?

Their core "appears" to be such, but I haven't seen many mentions of that.


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"None are so blind as those who will not see."

charlest,

To quote Jon Brandon (Major Action):

"Take the Bully series core for example. Anyone who looks at it will say its asymmetrical based on its shape and comparing the Top to the bottom and left side to right side, it sure looks different to me. But Columbia has stated that it is symmetrical. This can only mean to me that the density comparisons between top-bottom and left-right are the same, which gives the ball a very small MB number (under 0.0010 I think) which is why there is no marker for MB on the Bully series."

This is the way it was explained to me by a number of folks from San Antonio.  From sales to tech guys.  It IS asymmetrical, but not marked, due to the very low MB diff. The neat feature (one that can be done with most cores as I'm sure you're aware) is you can use MB layouts with this ball as well as common pin/cg layouts as well.  It's a little more responsive than 'true' symmetricals to those.

Bill
Bowling Services Unlimited
www.bsuproshops.com
Vise Inserts Staff
www.viseinserts.com