It is part of the golf vernacular. It’s ingrained in golf (nerd) culture—it’s a real thing.
But where does it comes from, how did it get here, and what is it really?
I’m here to give you some answers and introduce you to MP-20 family of irons from Mizuno.
Born from tradition, and the idea of creating the ultimate set of irons for every player, the MP-20 family is the next series of MP irons that will connect golfers to the “Mizuno Feel.” Speaking to tradition, and something I touched on when these were originally teased on social channels with #LayersOfFeel, Mizuno is going back in time to the TN-87s and reintroducing a copper underlay to their irons—all of them! (Before someone tries to correct me: yes, I realize that they have done this for more recent Japan market models )
What does this copper layer mean? Here’s the funny thing, even Mizuno has had a hard time trying to quantify it. Through multiple rounds of extensive blind prototype testing with all of their staff players, the irons with a copper underlay won on feel EVERY SINGLE TIME! How’s that for dominance?
But why? They are truly still trying to 100 percent figure that out. Mizuno has used its HIT (Harmonic Impact Technology), metallurgy analysis, and every test it can to try and figure out why. Engineers even went as far as trying to prove the hypothesis the copper underlay “feel” was based on nostalgia but time and time again Cu won in blind testing. At the end day, the human element was still the deciding factor because humans are the ones that ultimately hit shots.
This brings us to the flagship MP-20 (Blade) (The Ultimate Tour Blade as described by Mizuno’s Product Manager & Engineer Chris Voshall). Evolving from the tradition built into the MP-18, and taking design cues from historic models like the TN 87 and MP14, the MP20s provide more flow throughout the set from top to bottom leading to even more control over ball flight. This flow also increases forgiveness (please remember it’s still a blade) and launch in the longer irons, with an increased ability to flight the ball in the scoring clubs… all of this AND a thinner top line.
Now about that top line: it’s an extremely important part of the look of the club but, what many don’t realize is it also plays a big role in feel and acoustics too. Let’s simplify for a moment: think of a clubhead like hunk of metal—a cube—now when you hit that thick piece of metal on something it doesn’t reverberate much and when it does, it’s at a different frequency making it sound heavy and “thuddy,” or as some would say, SOLID.
Now imagine if that same piece of metal, same mass was stretched out like a saw blade. Have you ever hit something with the side of a large saw blade? It’s wobbly, loud, and generally unpleasant, that’s what happens when an unsupported part of a club gets too thin, it acts like an amplifier of bad sound, creating terrible feel. By blending a small channel (think MP5) with the classic looks of yesteryear you get a club that feels and performs like no Mizuno before it, and as I said, with a thinner look from address.
What’s all this talk of “Flow”?
Center of gravity and mass placement (or as a Mizuno Engineer explained to me “Vertical Moment of Inertia”). Since each club is designed individually, you need the center of gravity to shift throughout the set to help control launch/trajectory (or “traj” as the kids say), and make sure spin is also at an optimal level.
For the MP-20, it means long irons that are “easier” to hit (air quotes, because like I said before, it’s still a blade), and short irons that can be more easily flighted lower with greater spin and control. Just like with the MP-18s, Mizuno is keeping with the continuous reduced blade length into the short irons for a look preferred by better players and for improved grass and turf interaction.
But What About the Rest?
You might have noticed off the top I called it the “MP-20 Family.” Here’s why: In golf, like with any other industry, data is important. But it’s only as good as you use it and well…let’s just say Mizuno has been paying close attention to how golfers and fitters have been making combo sets over the last few years. It’s all about understanding what golfers really need and thanks to some proprietary data they went even deeper when it comes to designing each and every iron in this family to make sure its performance is maximized. This is why I continue to emphasize how each set has a flow, it to make sure each club in your bag is just right for you. Now to introduce you to the rest of the family members…
Mizuno MP20 MMC (Multi-Material Construction)
I know, you think you’ve heard this story before but…NOT LIKE THIS!
The new MP-20 MMC is a BIG shift in design, not just because of the Cu underlay, but a radical change in how the whole part is put together. I know it sounds very “big biz,” but in the world of manufacturing it truly comes down to how “parts” are manufactured. Now, with Mizuno, I will reiterate a well-known story. All of its forged irons are single-sourced from one foundry (Chuo) in Japan through a handshake agreement that has been in place for decades.
Now back to the MMC. Before the MP-20 the MMC always had one tiny design difficulty (not a bad one, just a truth) and that was the titanium piece in the back was the same size throughout the whole set. This lead to a set with almost constant sole width. That doesn’t mean previous generations were constructed poorly, but it just means there were improvements that could be made to how the set flowed (there’s that word again) from top to bottom…which leads us to the tech story.
For the first time in the MMC’d life, the titanium piece of the iron will actually vary in mass depending on the club. It will be broken up in the middle of the set to allow better CG placement, and like its blade cousin, improved turf interaction in the shorter irons.
What is also very cool from a build and engineering perspective is the way the titanium gets into the club in the first place. Here we go down a metallurgy rabbit hole, buckle up…
- Titanium has a mass density (rounded) of 4.5 g/cm3 – cubed
- Carbon steel has a mass density of (rounded) 7.9 g/cm3 – cubed
That means that from every cubed cm of steel volume you replace with titanium in the head, you save 3.4g… which might not seem like much, but in a 4-iron for example that has an average mass of 248g for (4) cm3 you save 13.6g or just over five percent. I realize this is DEEP into the mass property weeds, but when you think of what a club head weights and how every half percentage point matters, five percent is a lot! That’s more forgiveness, more MOI, more spin control, and overall better performance.
What is also very cool is all of these parts (titanium and tungsten) have ZERO chemical bond—no epoxy. They all fit snug based on the shrinkage rates of the different materials. Ti & W( tungsten – W comes from the ore Wolframite) shrinks less than the steel so as the steel cools around the titanium and tungsten pieces it creates a mechanical (solid) bond.
All of this together adds up to an iron that looks smaller than the previous version, offers more “flow” in CG, something we mentioned earlier that creates more forgiveness and control throughout the set, and at the end of the day it means a better-engineered version than the one before it.
Truth Break for a moment…
Let me make one thing clear, new sets are AWESOME! We are, and always will be, attracted to the latest and greatest but the player should still get fit and find out what works best. New will and should inevitably be better but the cost-benefit analysis should always be at the end of the day up to the individual golfer to decide and figure out what will end up in the bag to help lower scores.
The Hot Metal Mizuno MP-20 HMB
look AT THIS!!!
YES…you read that correctly. Mizuno is bringing Hot Metal tech to the MP line!
A hollow body blade looking iron using the same strong yet highly flexible Chromoloy material as the 919 Hot Metals except this time forged to create an iron like they never have before. The look and shape of a blade the speed of a Hot Metal.
Let’s break things down.
The look is clean as clean can be, from there the face of the HMB is thin and fast, while hidden inside the back of the club is complex geometry for both acoustics and precisely positioning mass. These will be the replacement for the MMC Fli-His but unlike that set, only going to the 6-iron, the new HMB will go all the way to the pitching wedge.
What is also different for the HMB vs. the MMC Fli-Hi is the way tungsten is used in the head to create different impact dynamics. The Fli-Hi had all the tungsten (20g worth) in one place in the head (low and towards the toe). The CG was still located right in the middle but through in-depth testing some players found that the Fli-Hi was a more difficult club to turn over and draw.
To improve the workability of the new HMB, the Tungsten was split into two 12g pieces (four more grams than previous Fli-Hi) and positioned into precisely formed pockets on the heel and toe in the back of the club. This allows the unsupported face to flex and makes the club more workable while still maintaining all the forgiveness you would expect from a hollow body iron built for speed. Seriously who doesn’t like the sound of that?
Since the new HMB is a full set and not just long irons, there is more to the tech story… here is comes… better flow and CG positioning throughout the set. This is hugely important for the mid and short irons where loft is already going to create spin so controlling ball flight and traj on approach shots is vital for scoring better.
This is again where the MP-20 Family discussion comes into play. Mizuno knows they are going to sell a lot more HMB long irons vs. blade and MMC long irons, so the entire family is designed holistically for every player to find each and every head that optimizes them on the course.
The Full Package
Like with previous generations going back almost a decade, Mizuno is keeping its industry-leading matrix of shaft and grip options available at NO upcharge. BUT… based on the growing demand for more exotic options the newly expanded shaft line up will include a few shafts that will come with a slight upcharge.
Whatever you end up being fit for, it’s important to realize that there has never been family of Mizuno irons designed like this, which could also mean you could be bringing home some new family members soon.