For golfers who are new to the game, there are lots of confusing terms associated with golf clubs. In addition, some of the explanations are inaccurate as well. One of which I want to address is offset. Many times I see the explanation that offset shifts the center of gravity further back in the head resulting into a higher ball flight. I want to dispel this myth and help those understand the function of offset better.
More…First, it is difficult to truly tell what offset does by itself. Typically heads with reduced, little or no offset tend to be designed differently from irons with more offset. Increased offset irons are designed as game improvement clubs, many of which have more upright lies, wider soles and shorter hosels positioning the center of gravity lower than comparable profiled irons. In this case, there are too many other parameters that have changed to honestly know what effect offset itself does to ball flight.
I am fortunate to have accumulated a lot of different irons over the years. One particular model was a Ping Eye II style iron that every manufacturer had their own version back in the late 1980’s and early ‘90s. Dynacraft’s version was called the “4140”. This was a progressive offset, cavity back design with the offset of the 5-iron being 3.5mm. Dynacraft also tooled up another design called the On-line. This head was made from virtually the same mold as the size, shape and profile were replicated. The only difference was the On-line featured no offset at all. Finally, two heads that was so similar to one another that the effect of offset can honestly be tested.
To understand how small difference this really is, look at the value. In metric, 3.5mm might seem like a lot, but in imperial measurements this amount to only 0.138” or just over 1/8th of an inch. The other important consideration is the ball position in the stance. Let’s say a golfer is at the driving range hitting off of the grass. The golfer drops or rakes a ball somewhere on the ground in front of them. From there he or she attempts to align themselves to the ball and their target. The ball may be nestled down in the grass or maybe sitting up on a little patch of grass. The ball will be a positioned in relationship from the distance of their body and also in relation between their front and back foot. I can tell you that the difference from one time to the next, the position will be greater than 1/8” difference, especially if the person is a higher handicapped golfer. Remember this very important point as clubs are played by humans and not swing robots.
With these two clubs in hand, they were measured very carefully to make sure they had the exact loft and lie, if not they would have been adjusted. As luck would have it, both measured 28° loft and 60° lie. Again these were older clubs as reflected by these angles. Each clubhead was built as a demo with the same shaft, shaft weight (within the gram), frequency, grip weight, while the shaft were carefully cut on a cutting jig to ensure the exact amount was trimmed from the tip and butt and then assembled to the same length and swingweight. The offset head required two small strips of lead tape to achieve the exact same weight.
What happens when these two clubs are hit side by side at the range? Remember what I said earlier about the position of the ball in the stance and how it sits does in the grass. The average golfer upon solid contact can hit the ball straight with the offset club, but also the non-offset club too. However, the tendency on the majority of the shots was that the offset club would yield a ball flight more left than the reduced or non-offset club (this for a RH golfer). The other thing that was apparent was the trajectory, with the non-offset club hitting the ball higher. To understand why can be explained by the position of the center of gravity.offset1.jpg
The center of gravity of the non-offset club is actually further behind the face of the club. The hosel does contribute a considerable percentage of the overall clubhead weight. The clubhead with more offset actually shifts more weight forward of the face rather than backwards. However, the center of gravity in relationship to the centerline axis of the shaft is further back in the offset head. This is what helps the clubface assist is closing the face. A reward center of gravity increases the center of gravity angle, therefore naturally closing the face.
I asked a few other very low handicapped golfers who are knowledgeable about the equipment and the swing to tell me if they thought offset hit the ball higher or lower. The best response I share is that offset tended to “trap” the ball at impact and effectively cause the ball to produce a slightly lower shot that will tend to go more to the left for a right-handed golfer. This has always been my experience as well with the same angles, shafts, shaft flexes, etc.offset2.jpg
There has been much debate over the years on the effect of offset. I am sure that I will hear arguments from fellow golfers who will read this and make a judgment based upon that golfer’s past experiences. My contention is the clubhead design, aside from the actual offset, may be the reason for their response. I simply wanted to conduct a scientific approach to limit all other variable as physically possible to test only one parameter – offset.