Balls of Same Weight have different CG and Pins?

[HughScot]

I was ordering a new ball today and said I wanted a light 14lb. So he asks me where I want the pin and I assumed that if the balls were alike in weight the CG and pin would be in the same place. Not true according to the pro shop guy. Apparently when the ball is finished they put it in something which tells them the CG or something..... I don't know so who can enlighten me on this procedure.

[bowl1820]

Here's from the bowlingchat wiki

Definition 3: Center of Gravity is not entirely accurate, the CG is typically a heavy spot on the ball for balancing purposes, the manufacturers place additional weight (known as top weight) to account for drilling, the punch mark approximates the spot where the ball when placed in a salt water solution "balances" itself, this is an approximation by the ball manufacturers as the "heavy spot" is down in the solution and the employee marking the ball has to measure 180* away from where they actually see it. The only true way to find this true zero zero point is to utilize a dodo scale.
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Also here's

Ball Construction and Dynamics,
Center of Gravity (CG)
The addition of the internal weight block will create an uneven distribution of weight in the ball. This imbalance will result in a portion of the ball being heavier. Identifying the heaviest portion of the ball is the first step in being able to effectively use this imbalance.

Center of Gravity (CG)
Since a portion of the ball is heavier than the rest, logic would dictate that gravity will pull the heaviest side of the ball down to the bottom of the ball. With the heaviest portion now located at the bottom of the ball – the ball is completely at rest. The axis running from the point touching the ground through the top of the ball is known as the center of gravity (CG). The whole mass of the bowling ball is concentrated around this axis.
An easy way of understanding the concept of CG is using a top as an example. A top is an unbalanced object with one part being heavier then the other. When putting the top into motion, it will eventually spin or rotate around a fixed or central axis. This point or axis (where the weight of the object is evenly distributed) is the CG.
Some ball manufacturers will determine and identify the CG on the ball by putting a punch mark into the ball. This mark is usually located somewhere within the label of the ball.

Pin-in and Pin-out
The terms “pin-in” and “pin-out” are used to describe the relationship between the location of the pin and the CG.

A ball is classifed as a pin-in when the pin is located within two inches of the CG of the bowling ball.

A ball is considered pin-out when the pin is greater than two inches away from that CG.

[Zothen]

It's called the Center of Gravity and it is usually placed on the ball where it is imbalanced. Depending how you drill a ball will cause the ball to be negative or positive weight,but,has a small amount of influence on a way the ball rolls. If you want a ball drilled pin up,pin down,etc the pro shop will order a ball with the pin placed around how they are going to drill it. The pin will also be short or long as well.

Zothen

[HughScot]

Thanks for the great info. I should probably worry less about technicalities and just practice more. I wonder how much difference this all makes for a guy with a 140 average who's trying to greatly improve? Oh well.

[billf]

You would be surprised how much it can help. Has the pro shop seen you bowl yet? A good driller can help match a ball and layout to what you need.
There are some who say a bowler has more to worry about than ball specs if averaging less than 200. I'm a believer that you won't truly know what you need to work on until you have equipment that matches how you bowl. Like how a coach has to adapt to a bowler, the equipment needs to adapt to the bowler as well, not the bowler adapt to the ball. Utilize the available experts and your average will go up 10-20 pins. Then work on your weaknesses and you will average close to 200 next season.