Question I just started bowling and I got a 13lb RH Tornado since I can't handle anything heavier. I got used to bowling a 10 lb house ball with a 2 hole grip open hand and bowling with 3 fingers still feels heavy. I grip the ball with the thumb all the way in an the other two with fingertips. I was advised to bowl like if I was shaking hands but its difficult to get a natural swing since it still heavy. Should I go lighter or change the inserts so that my fingers go in to the 2nd knuckle. Also what do the balls loose when going lighter to the generic cores?
Answer A fingertip grip gives you much more power and control. House balls make everybody equally bad so it's good you gave that up. If the ball fits your hand (it was drilled by a certified IBPSIA technician), it will feel like it weighs about 10% of its dead weight. It could just be a matter of you getting used to the weight.
Going below 14 pounds in ball weight is giving up a lot of hitting power at the pins. If you must throw only 13 and there is a medical reason you can't throw 14, okay, but don't go lower. Since the ball swings your arm rather than your arm swinging the ball, your comment about a 'natural' swing is counterintuitive. I would suggest you get a coach to take a look at your grip and swing plane. Good luck!