As part of the World Scientific Congress of Golf that was held in Vancouver this past summer, our team at PING gave a presentation about Pistol putting grips. We felt that some of the insights would be useful to the MyGolfSpy community. Here is a summary of that presentation.

Variations of the “pistol-type” putter grip have been part of the game of golf for much longer than one might expect. They are considered to be incredibly popular and have become the “somewhat traditional” shape of putter grip, according to the USGA [1]. This type of putter grip is characterized by a non-circular cross-section where the cross-sectional area increases approaching the butt-end and the axis of the grip tilts toward the player (figure 1). In some cases, these grips also incorporate an angled core.

There are a number of different ideas regarding the effect and purpose of the shape. The earliest references of grips incorporating some pistol design elements date back to the late 1800s and early 1900s. Two examples that show an increase in cross-sectional area, with a tilting of the axis toward the player are the Champion Grip and Murray Putter. The Champion Grip dates back to the early 1900s and was one of the earliest molded grips. It was also referred to as the “anatomical grip”. The Murray Putter dates back to the 1910s and incorporated a curved wooden shaft and grip. Inspired by ax handles, Avon Pardoe patented a similar grip in 1934. It was stated that it was designed to “ensure more accurate striking of the ball, and also a greater sense of security in holding the grip.” In 1936, McGregor started offering the Pardoe “Rel-Ax” rubber grip on their clubs. Another design to note is the Archie Compston putter, which incorporated a bend mid-shaft toward the player and was referred to as the “St. Andrews Bend”.

These early designs help shine some light on the inspiration that may have influenced the pistol grip designs we know today. As with these early designs, some manufacturers today suggest the larger geometry of a pistol grip’s end helps “lock-in” a player’s grip, leading to a more repeatable motion. PING’s founder, Karsten Solheim, viewed the pistol grip as an alternative to the Ballnamic bent shaft the company incorporated into iron and putter builds before it was deemed non-conforming by golf’s ruling bodies. His philosophy with the Ballnamic shaft was to incorporate a bend to align the grip with the center impact location of the club head, with the intention of reducing “twist” at impact [3]. Karsten began using the Golf Pride Informer grip on a number of his models as a result and eventually developed the PING PP58 putter grip to best replicate his Ballnamic shaft philosophies. Although this type of grip has been prominent for many years, there has been little-documented research exploring the effect of this type of grip on the delivery of the putter head during the putting stroke. A pilot study was conducted to explore whether there is a measurable effect on putter-head orientation at impact when comparing a pistol-type grip to a “straight” grip (uniform cross-section over the entire length of the grip).

Methods

Forty players carried out 5-putt sessions from 10 feet with two different putter grips installed on the same model of putter. The grips chosen for this study were the Golf Pride Tour SNSR Straight and Contour models, while the putter-head model tested was a PING Sigma G Tess. During each of these sessions, the motion of the putter was measured using the PING Putting app [4]. Additionally, players were required to use each putter to hit five 8-foot putts at one hole and five more at another. The miss direction and makes were recorded for every putt. Paired t-tests were used to compare the effects of the two levels of grip on specific dependent variables. The dependent variables evaluated in this study were the impact angle relative to address, impact lie angle, and impact loft.

Statistical significance was set at a < .05 for all tests. This is just a bit of academic speak that states how a difference in result is deemed “real” or “within the fuzz of the data”. Whenever two sets of data taken under different conditions (with a different club, for example) are compared, something called a p-value can be calculated. You will see this number reported in some of the graphs in the results section. When this p-value is less than 0.05, then we can say with a degree of confidence that there is a difference between the two clubs. If the p-value is above 0.05, then the conclusion from the test data is the variable in question is essentially the same for both conditions.

Results

Evaluating the delivered putter orientation data for each grip, there was a significant difference in impact angle between the two putters, as shown in figure 3, with the pistol grip being delivered more closed relative to setup. There was also a small, but statistically significant difference in lie angle at impact, shown in figure 4. The delivered loft showed no significant difference.

Additionally, when evaluating the miss/make data for the putts from 8 feet, the recorded data showed a slight tendency for the Straight grip to miss to the right more frequently than the Pistol grip (figure 5), but the difference was not “statistically significant”.

One element of the PING Putting App is something called a putting handicap. This looks at the consistency of different elements of a putting stroke and equates the variability in those elements to a handicap number. The consistency score was calculated for every player’s 5-putt session with each of the putters. The consistency of the closing angle, impact angle, and total consistency (which includes tempo, lie, and loft) is reported in figures 6 and 7. The first group consisted of players with low closing angles (less than 7.5 degrees on a 10-foot putt) which basically says they had less rotation in their stroke. Conversely, the players in the second group had average closing angles of more than 7.5 degrees.

Discussion

The results from this experiment suggest the pistol grip tends to promote a more closed face angle at impact when compared to a constant cross-section grip. Recorded misses on 8-foot putts show some evidence that the players are delivering the face more open at impact with the Straight grip, as opposed to setting up more closed at address. A previous study investigating the kinetics of the putting stroke using two putters with different CG locations relative to the shaft axis showed a similar result. A face-balanced putter delivered the face more closed relative to setup when compared to a heel-shafted putter [5]. It appears the design of the pistol grip orients the axis of the hands relative to the putter CG in a way that produces the same effect, making a heel-shafted putter play more like a mid-hang putter.

The most practical application of this insight is in putter fitting. If a player being fit finds a putter model they prefer, but they struggle with a miss in one direction or another, using a grip that is straight or has a pistol design could help fight this miss tendency. For example, if a player loves his Anser model with a non-pistol grip and is fighting a push, a pistol grip may potentially help. Additionally, the consistency results may suggest players with more rotation in their stroke could perform more consistently with a straight grip on a putter like a Tess, since this maintains the “toe-hang” nature of the design (figure 7). For players with less rotation in their stroke, a pistol grip may be the best option on a putter like a Tess, since it appears a pistol grip makes the heel-shafted putter play with a little less “effective hang”, leading to better consistency (figure 6).

References:
1. USGA (2018) Guide to the rules on clubs and balls, United States Golf Association. http://www.usga.org/rules/equipment-rules.html
2. Ellis, J.B. (1997). The Clubmaker’s Art: Antique Golf Clubs & Their History. Oak Harbor, WA: Zephyr
3. Ellis, J.B. (2017). And the Putter Went … PING. New York: C&C Offset
4. Cottam, R.J., Wood, P.D., Henrikson, E.M. (2017) Systems, methods, and articles of manufacture to measure, analyze and share golf swing characteristics U.S. Patent No. 9,821,210. Washington, DC: U.S. Patent and Trademark Office.
5. Mackenzie, S., Henrikson, E.M., (2018). Influence of Toe-Hang vs Face-Balanced Putter Design on Golfer Applied Kinetics, ISEA 2018 Engineering of Sport, Brisbane March 26-28 2018