Hi Andy,

It's a combination of two things, hitting the sweet spot dead centre middle of the face, this naturally creates maximum compression on the ball because to hit the spot correctly takes a good swing.

The rock feeling can be many things all of which doesn't involve hitting the sweet spot. Hittling low in the face gives most vibration, toe shots tend to twist the club in your hands and finally the s****k just scares the living daylights out of you.


Ian.