Sphiz 21, the C.G. is the heaviest spot on the ball, the Pin is the heaviest spot on the inside of the ball, it actually holds the weight block in the mould when they pour in the reactive urethane liguid.
WE were told many years ago, when the Pin is 1" from the C.G. this means that the weight block is 1/64" off centre. The early Hammers had the pin almost on the C.G. ( J. P. Fabernich was the man that came up with the idea to put the weight block in the centre of the ball) the Hammers were the first to have Pins.
What a 5" pin means is that the weight block is 5/64" off centre, the ball companys started to off centre them on purpose, because some people found they could get more action out of them. This all means that the weight is shifted more to one side, thus you have a ball that has a higher mass bias. Mass bias is only a minor weight and has a small influence in the ball reaction, it usually means the ball holds it's action a little longer, this may be a plus, but if you are bowling on heavily oiled lanes, than you want a ball to turn-over quickly.
All the weight shifting has to do with wobble, as the ball wobbles down the lane it is not able to turn until with the help of friction the weights start to line up, than as the Americans would say the ball turns over, now it can hook. High R.G.'s in a ball, means it can create more flares, the flares on a ball are an indication, that the weights in the ball are starting to line, up as it travels through the oil.
Willey.