Wilson Staff D9 Irons

Wilson Staff D9 Irons – Key Takeaways

• Wilson’s longest iron gets a little longer.
• Features computer-optimized Power Holes and lower center of gravity.
• $649.99 in steel, $749.99 in graphite
• Available Jan. 26

The new Wilson Staff D9 irons have, relatively speaking, a hard act to follow.

D9’s game improvement predecessor – the D7 – was Wilson’s best-selling iron post-lockdown even though it was in its second year. Wilson touted D7 as its longest iron ever and our Most Wanted testing confirmed that. D7 was the second-longest iron set tested last year, just behind the Callaway Mavrik.

Length isn’t everything, but it is something. And when you’re Wilson, getting attention in the hitting bay is maybe the best way to get the consumer’s attention. And if a lot of distance is good, then a little more than a lot is even better.

So what makes the Wilson Staff D9 irons longer? Well, new Power Holes and an even lower CG are two big reasons along with a little help from a loft-bending machine.

Let’s unpack this suitcase and see what’s inside.

Wilson Staff D9 Irons – Built for Distance

While the Wilson D7 irons were the second-longest irons tested in last year’s MyGolfSpy Most Wanted Game Improvement Iron shootout, they ultimately finished in the bottom half in strokes gained.

Oddly – or maybe not so oddly – none of the four longest irons in the test finished in the upper half in strokes gained.  Of those four, the D7 was the best overall strokes gained performer.

That’s why it’s a relatively hard act to follow. And that’s why Wilson brought in its supercomputer to help with the heavy lifting.

“What we did here is let the computer give us insight into how to improve performance,” says Jon Pergande, Wilson’s Manger of Golf Club Innovation. “We gave the computer the ability to manipulate CAD models through different designs and then run them through simulations for ball speed and distance.”

Wilson’s software uses more than 100 processor cores of computing power in its intelligent, generative design modeling. And that’s what led to Power Holes 2.0.

Optimizing Your Power Holes

Golfers fall into two camps when it comes to Power Holes. There’s the “are-you-kiddin’-me-those-are-friggin-ugly” camp. And then there’s the “if-you-see-the-power-holes-while-you-swing-you’re-doing-it-wrong” camp.

Power Holes are Wilson’s way of separating the iron face from the sole to allow for maximum deflection and ball speed. Every OEM is trying to do the same thing with their respective technologies whether it’s through variable face thickness, Thru-Slow Speed Pockets or COR-Eye. While Power Holes have been around since 2016 and the C200 irons, this iteration is the most refined yet.

“D7 had three rows of power holes in the long irons, down to two progressing through the set,” says Pergande. “But those were very orderly, very symmetric, very engineered. We came up with those as humans.”

The Power Holes have been noticeably toned down on the Wilson Staff D9 irons. There are only two rows and they’re much less obtrusive and, according to Pergande, more effective thanks to the computer.

“The D9 Power Holes are not symmetrical, they’re not the same size,” he says. “The heel side holes are a little wider than the toe side holes. And that was an interesting insight that said we had to free up the heel side of the face to add more performance to the entire face.”

It’s been a long, strange trip for Power Holes. The C200 irons and metal woods had more Power Holes than Tiger has had back surgeries and each iteration since then has seen more refinement and – in the case of the metalwoods – elimination.

“We found the biggest bang for the buck is to leave the Power Holes in the sole,” says Pergande. “That’s where we get the biggest performance benefit. They’re not as effective on the topline.”

The CG Race to The Bottom

Ball speed/face deflection is a leading character in every game improvement iron release we see. And every release has the same co-star: the lowest center of gravity possible. The Wilson Staff D9 irons are no different.

If you’ve been even a casual MyGolfSpy reader, you know the lower an iron’s CG, the easier it is to launch an iron high and, presumably, far. The target game improvement player needs help getting the ball in the air so a low CG is helpful. And lowering the CG while strengthening the lofts helps that player achieve some distance.

“We made a conscious choice to get the CG as low as possible,” says Pergande. “The idea is to elevate the launch angle, reduce spin and get the hottest face possible.”

The CG on D9 is roughly 50/1000^th’s of an inch lower than it was on D7. That may not sound like much but Pergande says it’s fairly significant in the world of iron design.

“With only two rows of Power Holes instead of the three we had with D7, we’re able to push a lot of material very low.”

As mentioned, Wilson’s Intelligent Design process moved those Power Holes closer to the heel with D9. A paradox of modern game improvement irons is they tend to be right-biased since there’s more face surface and therefore more face flexibility towards the toe. Our recent articles on the PING G425 and the TaylorMade SIM2 Max irons discuss this in greater detail. And like PING and TaylorMade, Wilson is working to counteract that right bias. By shifting the Power Holes heel-ward, Wilson is offsetting the inherent face flex towards the toe.

 MOI and Descent Angles

Lowering CG does come with an MOI tradeoff, however, especially in the longer irons.

“The MOI-launch condition tradeoff isn’t an all-or-nothing proposition,” says Pergande. “If you improve launch conditions, even if you hit it slightly off-center, you’ll get greater distance because you’ve reduced spin and because of the launch condition you’ve achieved.”

Pergande says the MOI drop-off for the Wilson D9 irons is pretty minor and is more than offset by the size of the head and the low CG.

Make no mistake, the Wilson D9 irons are among the strongest-lofted game improvement irons on the market. That, plus inherent low spin, makes the low CG/high-launch characteristics kind of important if you have any hope of holding a green.

“We want to hit the ball as high as we can so it’s coming down as steeply as possible,” says Pergande. “That way, the ball isn’t getting away from the player. It’s hitting the green and staying there.”

General wisdom says anything over a 40-degree descent angle with a 7-iron is enough to hold most greens this side of Augusta National. Pergande says the descent angle with D9’s 7-iron is in the mid-40s while the 5-iron descent angle is right around 40 degrees.

Specs, Price and Availability

The Wilson Staff D9 irons are designed for distance with a 27-degree 7-iron. If you’re a card-carrying member of the Loft Police, feel free to go apoplectic. The standard 7-piece set starts with a 21-degree 5-iron and ends with a 47-degree gap wedge.

An 18-degree 4-iron and a 53-degree sand wedge are optional and available only through Wilson’s Custom Order department.

The standard steel shaft is the new KBS Max Ultralite which is not yet listed on the KBS website. We can only presume it’s a lighter version of the MAX which KBS touts as a high-launch, high-spin shaft. The stock graphite shaft is the Tensei AV Silver which Mitsubishi describes as mid-launch/mid-spin.

The stock grip is the Lamkin Crossline Genesis.

The Wilson Staff D9 irons will be available in both left- and right-handed models. If you’re also apoplectic over pricing, the D9 might just make you smile a little. The 7-piece steel set will retail for $649 while the graphite set will sell for $749.99.

Wilson is also offering D9 in a women’s model. The 7-piece set (6-iron through gap wedge) features the Aldila Quaranta graphite shaft as stock along with the Wilson Staff Women’s Performance grip. It will sell for $749.99.

They’ll be available at retail and on Wilson’s website on Jan. 26.