If you have the opportunity, use a ball from a friend or one from the rack that fits your span, that's important. Try a 14 for a game or two, then a 15. If there is no pain, strain then a 15 will probably work for you. Try that a few games and do the same with a 16.
I think some folks start out with to heavy a ball, have elbow/wrist problems and then have to drop weight, that's an expense you don't really want. Depending on the build, strength, I tell my customers to try a weight ( usually 14 or 15 ) and see. There's not much reason to go to a higher weight just so you can say I use a 15 or 16# when in a few weeks you develop problems. Telling you online is hard, I can't see your build, but an old rule is ten percent of body weight is the weight of ball.
I don't hold to that, but some do. Best thing I can say, go talk to your pro shop guys. They might have a used 15 or 16 around they'd let you use for a game or two. They will be able to help you out a lot more than someone online .
JMO
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AZ Guy aka: R & L Bowlers Pro
rlbowlerspro@cox.net
www.rlbowlerspro.comSleep is over rated.