Since the majority of golfers are not touring professionals, the new groove dimensions may not have an effect on your golf equipment for as far off as 2024. The guidelines can be confusing, but the rules are simple if you consider them only based on the type of golfer you are. A touring professional needs to be using these new grooves this coming January, but for the most part, all other golfers can continue using their existing clubs until 2024. The big “however” is if you purchase a wedge manufactured after January 1, as the new equipment must incorporate the new grooves if they are to be R&A and USGA conforming.
Countdown for clubmakers
For custom clubmakers, you have until December 31, 2010 to assemble your heads manufactured before January 1, 2010, in order to be grandfathered under the old grooves clause. The R&A and USGA have granted all OEMs, professionals and custom clubmakers an entire year to get those old heads assembled.
Seeking tough rough
Now that we clearly understand who can and cannot play with the old grooves, the question that remains is: why is there a need to change the groove dimensions in the first place? After extensive testing, the R&A and USGA determined that ‘highly skilled’ golfers were not being sufficiently penalised for missing the fairway with their drives. With the older groove dimensions, a ball hit out of the rough has as much spin as a ball struck from the fairway, thereby inflicting no penalty to the golfer. In fact, if the rough is wet, there is more measurable spin using the old maximum groove dimension compared to a shot hit from the fairway.
In the end the ruling bodies felt it was necessary to reduce the volume size of the groove by approximately 50%. Under the new rules, the grooves can be as deep as previously (.020”) or as wide as previously allowed (.035”), but they cannot reach both these maximum dimensions. Since there must be less volume to the groove, you can maintain the old groove depth while reducing the width by approximately half – or you could stick with the old groove width and reduce its depth by half. The only way to maintain the original width and depth is to turn the groove into a “V” instead of a “U” or square groove. In addition, the radius of the groove edges must be much softer and the spacing of the grooves also influences the total volume that a groove is allowed.
It is up to the equipment manufacturers to determine the most efficient groove design for clubs with 25 degrees of loft and higher. The major OEMs have spent a great deal of time testing prototypes with a variety of groove configurations to arrive at the dimensions they will begin using in 2010.
On the spin
Our own testing at Golfsmith has indicated that most amateur golfers are unable to tell a difference in performance between the older wide grooves and the newer, conforming narrower ones. For the touring professionals there is a difference. Of those who we’ve spoken to, changing to a softer ball cover has countered the difference in spin rates around the green. Ultimately though, a golf ball cannot compensate for the range of shots a player will be up against due to the varying course and weather conditions.
