MPF Iron Ratings for 2007
As an addendum to the Maltby Playability Factor for irons book, Ralph has updated ratings for all new irons. Click on the link below to download and view the latest iron MPF ratings.
Coefficient Of Restitution (C. O. R.)
A DISCUSSION ON BETTER UNDERSTANDING C.O.R.
C.O.R. is easier to understand with a few additional examples and a little deeper explanation. First, recognize that when two objects collide there are 3 basic conditions of impact that exist. There are perfectly elastic collisions, perfectly inelastic collisions and everything else in-between.
An almost perfectly elastic collision is best demonstrated by two ivory que balls. When they collide, no or very little mechanical energy is dissipated so the speed-in of one ball is equal to the speed-out of the other ball after the collision.
How Moment of Inertia (MOI) Affects Driver Playability - should you buy a square driver?
Introduction
Two of the USGA limitations on driver heads are size and MOI. The maximum driver head size is 460 c.c. plus a 10 c.c. tolerance making the absolute maximum legal size 470 c.c. The term c.c. stands for cubic centimeters. The maximum allowable driver head M.O.I. is 5900 g-cm² plus a tolerance of 100 g-cm² making the absolute maximum driver head MOI 6000 g-cm². The term g-cm² stands for grams per centimeter squared.
Design Quick Links
Understanding and Fitting Driver Face Angle and Loft
An explanation of driver loft and face angle.
