The gradient line balance hole is from your pap and mb, whether it's a asymmetrical or symmetrical/marked or unmarked mb! The pap indicates the P1 location and the mb indicates the P4 location, the P2 and P3 are equidistance from the other two locations/P1 & P4! These locates are for the location in the core/weight block where you're removing weight. If you reverse it and go from pap to pin then you're drilling weight out of the top of the core/weight block, which shorten it so you're actually lowering the differential increase of raising it. If you look at Mo's chart, you can actually create a higher mb even in a symmetrical weight block by the location of the weight hole. I place weight holes on a line from the grip center, through the cg, 1" past the val and try to keep it at least 3-3/8" from the pin so I'm drilling more out of the side of the core/weight block. Please place a double piece of tape in the location where you're going to drill and roll the ball to make sure it's not going to hit the hole. Depending on the track and the ball flare, this will make sure of the flare before you place a hole in the ball to make sure you have enough room. Good luck to you, Bruce
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"Train a child up in the way they should go and when they are old they will "BOWL TO WIN", KEEP ON "TRACK", HIT LIKE A "HAMMER", AND "BOWL THE WORLD OVER" and not turn from it.
Bruce Campbell
USBC Bronze Certified Coach
IBPSIA Certified Technician