MP-20 HMB: Players iron feel to the players-distance category

By Drew Mahowald -- 2nd Swing Staff Writer

The highly-popular MP iron line from Mizuno has created thousands of brand loyalists over the years. For decades now, Mizuno MP irons have been among the most popular for tour professionals and talented ball strikers.

Mizuno’s patented Grain Flow Forging process has helped it become one of the golf industry’s leaders in manufacturing exceptional players irons. The MP line -- and a select few models in the JPX line -- boast the indescribable, unique feel that the Grain Flow forging process produces.

The only issue is that the exceptional feel from the Grain Flow forging process has been nearly impossible to implement into distance-oriented irons. The players-distance iron category has been created largely for that purpose, to create a distance iron that also has players iron feel.

This feat has proven tough to accomplish. Many manufacturers have produced excellent players-distance iron models, but very few, if any, truly possess the same feel as a players iron.

With the MP-20 HMB irons, Mizuno has brought its patented Grain Flow forged feel and explosive ball speeds together. 

At address, the MP-20 HMBs look almost like a players iron. Mizuno used the same formula to create the HMBs as they did to design the MP-20 Blades, the main difference being that the MP-20 HMBs possess a larger footprint. This extra mass is positioned largely in the sole, while additional tungsten weighting has also been placed in the heel and toe side of the clubhead. In other words, most of the extra mass is hidden at address.

The generous sole width and additional tungsten weighting help to lower the center of gravity, which results in improved launch, higher MOI, and increased performance on mis-hits.

In order to supply added distance, Mizuno engineers took a page out of the design of the JPX-919 Hot Metal Pro irons, which have received high praise for the distance they produce.

The clubfaces of the MP-20 HMB irons, like the JPX-919 Hot Metal Pros, are forged from ultra-thin, high-strength Chromoly 4140M. This material is extremely thin but also extremely strong, which delivers excellent face flexing for more distance all over the clubface, not just on contact made in the center.

With all of that said, where Mizuno is trying to distance itself from the pack in the players-distance iron category with the MP-20 HMBs is in the feel department. The irons have been constructed with Mizuno’s patented Grain Flow forging process, known for decades for producing exceptional feel.

However, Mizuno made a tweak to the construction with the MP-20 series. A few months ago, engineers decided to create a few prototypes that included a plated layer of copper underneath the nickel chrome top layer. The copper layer was a staple in some of Mizuno’s classic MP irons but has not been used for several years.

Mizuno conducted blind testing with tour professionals at a PGA Tour event this season, asking players to hit multiple prototypes without knowing which models included a copper layer.

The players almost universally preferred the models with the copper layer. So, Mizuno began constructing the entire MP-20 line -- MP-20 HMB included -- with the plated copper layer.

This produces perhaps the best-feeling players-distance iron available in golf. Add in the additional sole width, tungsten weighting, and high-strength Chromoly face, and these irons check all the boxes in their category.

I recently had the chance to test the Mizuno MP-20 HMB irons at 2nd Swing’s Minnetonka Tour Van location and at a local driving range. Having played Mizuno irons for several years, I was eager to see what Mizuno’s latest technology could deliver.

For the test, I was able to hit a few shots with an MP-20 HMB 7-iron and 4-iron. Using Trackman technology at the Minnetonka Tour Van, I was able to compare the numbers to what I usually get from my stock 7-iron and 4-iron.

For reference, my stock 7-iron carries about 175 yards with roughly 123 miles per hour of ball speed and 7,000 RPM of spin.

I decided to hit seven well-struck shots with the 7-iron to dial in averages from a solid sample size. Trackman technology provided the following readings: 183.7 yards of carry, 128.1 miles per hour of ball speed, and 6,347 RPM of spin. That’s over eight yards of carry distance and about 700 RPM fewer of spin.

Meanwhile, my stock 4-iron carries about 205 yards at 138 miles per hour of ball speed and just under 5,000 RPM of spin. The MP-20 HMB 4-iron, however, carried 216.6 yards with 143 miles per hour of ball speed and 4,412 RPM of spin.

It’s worth noting that my current set is a split-cavity players construction and has slightly weaker lofts than the MP-20 HMBs. Nonetheless, the distance gains I received on Trackman are significant and are a result of the technology Mizuno has packed into their newest players-distance iron model.

I must also add that, after finding a local driving range to hit a few shots, I was surprised by the combination of forgiveness and workability the MP-20 HMBs deliver. As a low single-digit handicap player, I make solid contact on most of my iron strikes -- but I’m far from perfect. The HMBs maintained my general flight trajectory and barely dropped off in terms of distance when I missed the center of the face.

Additionally, I tried to get cute hitting a few fades, draws, slices, and hooks, as well as some controlled knockdowns. It was much easier than I was expecting to control my trajectory, which should appeal to low-handicap or even scratch golfers.

And of course, the feel was exceptional. The copper layer plating beneath the top nickel chrome layer lives up to the hype. The MP-20 HMBs felt better than my current gamers do, which is saying something considering my current gamers were constructed with Mizuno’s Grain Flow forging process a few years ago.

Thousands of golfers are switching to the players-distance iron category and with good reason. It’s the perfect balance between a players model and a game-improvement model. Mizuno has delivered several excellent models to choose from, as have other manufacturers.

However, if you’re looking for the best-feeling players-distance iron that still delivers the added distance and forgiveness, the MP-20 HMB is the winner.