There’s a common argument with Game-Improver irons that’s been given with every new release in the category. The framing may vary depending on who’s making the point but it breaks down to this: stronger lofts make the ball go further but you always lose out with height. It may be true with some GI irons, but there’s a new technique being used in the construction of the new Mizuno JPX 925 Hot Metal irons that may make that argument null and void.
Last generation’s JPX 923 Hot Metal is a tough act to follow. when it arrived in 2022, it was seen as a true Mizuno golf club within the more forgiving category, offering looks and feel more like a classically designed head but with modern materials that benefit golfers who struggle with ball-striking consistency.
Fast forward two years and Mizuno have released the 925 family, which looks to improve upon a formula that has been one of the company’s most successful to date.
The engineers at Mizuno have, for the first time for the JPX line, used Multi-Material Construction in an attempt to redefine how we expect these kinds of irons to play. Utilizing tungsten weight in the mid and long irons, the 925 Hot Metals – whether the standard, the Pro, or the Hot Metal HL – have been created to maintain ball speed while creating a steeper landing angle. Tungsten, a heavy metal, is used to pull mass lower in the head, bringing the Center of Gravity lower with it.
Mizuno says that this change means that they can include the stronger lofts that will still see the distance you expect but increase the apex height and launch angle of your shots. The ball speed gained also helps you achieve a higher flight on the course, and this aspect of the head is as close to illegal as it can get with the return of the Nickel Chromoloy saw in 923.
The chromoly blend has been enhanced this year with Mizuno’s new CORTECH Contour Ellipse Face. Angled from low heel to high toe, where the majority of misses will occur, the 1.2mm multi-thickness creation is 30% thinner than before, helping you gain an advantage wherever you might strike.
Max Speed, Max consistency
- Consistent distance across the face
- Extra height makes this iron incredibly playable
- Can fit a wide range of golfers
- The sound is not as soft as Mizuno claim
Lofts 4-PW / GW / SW Stock Shaft Nippon NS Pro 950 Neo / UST Mamiya Recoil DART ESX Stock Grip Lamkin UT+ Left Handed? Yes
- CORTECH Contour Ellipse Face
- Multi-Material Construction with Tungsten Weighting
- Chromoly 4140M
- Seamless Cup Face
- Harmonic Impact Technology
- White Satin Brush Finish
From my time with the Hot Metal, I’m pleased to say it’s lost nothing of its strength; power is here for any that want it, with a flight that reminds more of my driving iron than a typical mid-iron.
That’s not to say I mean flat or low. On a launch monitor, I tested these against the 923 Hot Metal and saw 1.2mph more ball speed (impressive, considering the material is ultimately the same) but with a 0.8º increase in launch angle. This number combination resulted in four yards of carry distance gained, but with seven more feet of height to come into the greens with.
Equally as important, the Ellipse design, along with the new 360º seamless cup face technology kept my misses tight for front-to-back dispersion, an element that shouldn’t be undersold when considering the golfer these irons are aimed at. But distance and control are not the only elements to consider, especially as this is a Mizuno-made golf club…
When you invest in a set of Mizunos, there comes a certain expectation. Golfers want to see clean looks with a timeless look to them, but the sound is equally important. Mizuno themselves say that feel relates more to the sound of your equipment than it does from vibrations that travel into your hands, certainly something they’re not wrong about.
With that in mind, the 925 Hot Metal features Harmonic Impact Technology. This translates into head geometry engineered for ideal feedback. The technology utilizes Acoustic Sound Ribs to stabilize the top line, providing rigidity that fine-tunes the resonation and improves feel. These ribs are backed up by a Sound Bar that changes sound pressure to remove certain undesirable frequencies. You can see the bar on the rear of the club head and it’s been designed to take out any ‘clicky’ sounds you’d normally associate with this style of iron.
Despite Mizuno’s hard work, I’ve found the reality to fall down with this performance aspect. While I’m not expecting the smoothness of Mizuno’s headline butter knives, the Pro 241, with all the work that they’ve done to innovate in this space, the 925 hasn’t hit the mark for me.
This is not a reflection on the performance, I’ve seen some demonstrably better numbers from the Hot Metal as we’ve seen, but striking these irons hasn’t been the subtle noise that I was hoping for. The power of the head is reflected in the sound with a loud echo coming after impact. I wouldn’t say this is any different from another iron in this category, such as Callaway’s Ai Smoke, but after seeing and hearing Mizuno’s claims regarding feedback I’ve come away a little disappointed.
The JPX 925 Hot Metal is a great iron. It offers the same impressive power as the 923 did but makes gains where Mizuno have targeted, with additional launch increasing the playability of this iron beyond that of a simple distance-first iron set.
To look down at, the top line isn’t ludicrously wide and the sole feels like it straddles a good middle ground between bouncing off the floor and getting ‘stuck’ into the floor. The badging on the back is close to the previous Hot Metals, with simplicity at the forefront, but you never see too much cavity at address, even in the longest irons.
Comparing short irons and long irons on the golf course, the consistency in apex height is a serious selling point for any iron let alone a game-improver. Knowing you’re going to see the same flight going from a 5i to a 7i to a 9i means more predictable run out and release from your irons when attacking into greens – essential for playing good golf and shooting better scores.
My only letdown is the feedback. If Mizuno hadn’t made a point regarding how they’d worked on the sound and vibration, I doubt I’d even have raised it as an issue. There’s nothing between these and other iron sets from the category, in that they sound powerful on contact. But when you tell me I should get a softer, tighter feel from a new iron, I expect it. It’s not enough to lose Mizuno points, as this is down to my personal preference, however, I’m not going to be recommending this club to anyone wanting something along the lines of Mizuno’s forged back catalog.
For everyone else who knows not to expect a forged blade comparative, I’m happy to recommend what might be the fastest and highest game-improver irons on the market today.
As nice as they are, there’s no escaping the 925s are the 5th generation of the JPX900 family. We’ve seen similar ideas run through the five-model family (two of which are forged and three cast Hot Metal models) before, so this time around appeal is wearing a little thin. Where in the past there’s been a serious reason to convince golfers to spend their money with Mizuno rather than opting for a TaylorMade Qi, Callaway Ai Smoke, or Ping G430 it’s getting harder and harder to put the Mizuno models in front of the competition. Especially so as the model is cast from springy chromoly steel and doesn’t come with the pedigree of a Mizuno forged iron.
Our test data has the model (from the same 28° 7-iron loft) outpowering the JPX925 Pro by 0.9 mph of ball speed and 3 yards of carry distance which shouldn’t be enough to be a deal breaker for either iron but gives an excellent idea of the impact smaller, less forgiving irons have on overall performance.
Our test pro’s data shows it would be entirely possible to throw a blanket over shots hit by the JPX925 Hot Metal, Callaway Ai Smoke, and TaylorMade Qi as the numbers for all three were very similar across the board when hit at reasonable speed. Golfers who don’t possess tons of speed should have their heads swayed by the JPX925 HL which produced 702 rpm more backspin, a yard more shot height, and a 1.9° steeper descent angle, all numbers which will help flight shots for more distance and stopping power, to up playability.
Iron7-Iron LoftBall SpeedLaunch AngleBackspinHeightDescent AngleCarry DistanceShot AreaJPX925 Hot Metal Pro28°128.3 MPH12.8°5180 RPM28 YDS41.7°189 YDS330.4 SQ YDSJPX925 Hot Metal 28°127.4 MPH13.2°5357 RPM28 YDS42.2°186 YDS246.6 SQ YDSJPX925 Hot Metal HL31°127.2 MPH13.7°5882 RPM29 YDS43.6°184 YDS295 SQ YDS
Lewis Daff joined the Today’s Golfer digital team in 2024, having spent more than a decade in both big box golf retail and independent stores, working as a club fitter and builder.
Experienced with every level of golfer, from beginner to professional, he has achieved Master Fitter and Builder status with most major manufacturers, including Mizuno, Taylormade, and Callaway, helping him to cement both a wide and deep knowledge base. Lewis specializes in Clubs, Shafts, Training Aids, Launch Monitors and Grips.
In Lewis’ bag is Titleist GT3 Driver (9º) with Fujikura Ventus Black, Titleist GT2 Fairway Wood (15º), Wilson Staff D9 Forged 3-iron, Srixon ZX7 MKii Irons (4-PW), Titleist SM9 Wedges (52º, 60º), Toulon San Diego Putter, and Callaway Chrome Tour Ball.
Talk to Lewis about why steel shafts are now dead and graphite is the only way forward or any other equipment you’d like to debate via his email.
