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Last updated: May 26, 2022
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Muscleback irons are designed for elite players who want to maximize their ability to curve the ball, the feel of the iron, and get more distant shots. These irons have an ultra-soft feel that is realized by crafting one piece of iron from soft steel.
When choosing the best muscle back iron, your focus should be on the stiffness of the shaft flex, the materials the iron is made of, and the loft and lie angle. But if you don’t know all the basics of a muscle back iron, the irons listed below are a selection of the latest and the best models that have hit the market. Take a look at them, and you’d see how they can improve your shots.
"Created to offer precision and distance, these irons offers more playing comfort while maintaining a high degree of accuracy.Stiff or extra stiff shaft flex options.Ultra-light urethane foam inside the head.Enhanced sweet spot."
More features: set of 8 irons; soft copper underlay; shorter and more compact appearance; thicker behind impact
The Mizuno MP 20 HMB is our Editor’s Choice and our overall best muscle back irons, thanks to its clubhead design and shaft flex that conveys significantly more feeling than many competitor models. Here, the HMB stands for Hot Metal Blade, which tells how the iron is forged. These irons also have the nickel-copper interlayer, but the partially hollow heads can affect the feel, and the feedback cannot compete with their MP-20 alternatives. The situation is somewhat different with the PW and iron 9 since softer carbon steel was used for these. However, it should be noted that the PW and 9 iron appear a bit heavier than the rest of the golf clubs.
Although the heads are slightly larger than those of the Mizuno MP20 MMC set, the proportions are consistent. There are also slight differences in the sound of the differently constructed HMB irons. All in all, the contact is soft yet solid. The golf clubs performed exceptionally well on the course, especially when it comes to having to accept little loss of distance on badly hit balls.
Why are we impressed?
It’s plated with soft copper and finished with nickel chrome
Great impact feel and feedback thanks to the cooler underlay
It has a strong forged metal structure that vibrates less
What negatives must you be aware of?
There is no left-hand design
It’s more expensive than competing models but worth it
Materials: alloy steel shaft; tungsten-infused, multi-material club
Golf club loft: 18°–24°
Lie angle: 60°–61°
More features: 360 Face Cup for faster ball speeds; Urethane Microspheres; 2-year warranty
Callaway took three years to create the Callaway Apex 19 irons, the successor to their 2016 Apex golf clubs, and it’s all worth the wait. The Callaway Apex 19 Smoke iron is a tungsten-infused, multi-material construction that allows clubs to position the center of gravity precisely for better ball flight. The precisely placed center of gravity and the flexible 360 Face Cup create the ideal launch angle and ball flight. VFT (Variable Face technology) is the Face Cup. The microspheres guarantee maximum performance. In addition, VFT lets you control the spin and make aggressive shots in your score clubs.
Apex 19 irons were designed for experienced golfers and are more challenging than game improvement irons. However, they are competitive with irons for low handicap golfers. One of the things which make this better than the Mizuno MP 20 MHB is that this one has a left-hand version, and it’s much more inexpensive, although this isn’t a set but a single iron.
More than one million microspheres (microparticles) are placed behind the clubface to absorb vibrations. Microspheres that collapse on their own when the face rebounds create maximum ball speed and reduce vibration, especially on thin shots that would typically reflect shock into your hands. Combining it with a 1025 carbon steel body gives you a solid yet heavy feel for a pure hit iron.
What do we love it for?
The irons offer the smoothness and performance of a cast iron head with the flexibility of a forged iron
Has the same feel you expect from a premium Callaway iron
More features: Thru Slot Speed Pocket; ultra-light urethane foam inside the head; hollow body construction; Inverted Cone Technology for an enhanced sweet spot; 2-year warranty
Staying one step ahead of its competitors, the American brand TaylorMade has developed its first range of utility clubs, the TaylorMade SIM UDI. It is created to offer precision and distance in 2 versions (18° and 20°). It thus makes it possible to replace the iron 2 or 3 in a golf bag. In addition, the TaylorMade SIM UDI offers more playing comfort while maintaining a high degree of accuracy.
The TaylorMade SIM UDI and SIM DHY, released together, are intended to replace the long irons in a golf bag. These two clubs have a C300 forged face with an inverted cone in common. It provides more sensation to the strike and an adequate power return to gain distance. But if these two models are tolerant, they still have some minor differences. While particularly easy to play, TaylorMade SIM UDI and SIM DHY hybrid golf clubs each have their character. The DHY model facilitates high balls and counters the slice with a slight offset. It is balanced so that the nature of the trajectory is high and easy to access, even in the densest roughs.
On the other hand, the UDI model was developed to offer more penetrating ball trajectories, ideal for players with a great swing. A little less tolerant, the head of the SIM UDI promotes effects that will help you get out of the most delicate situations. Finally, the SIM UDI is also regarded as a long-distance model if you’re looking for the best 2 irons.
What makes it stand out?
Ideal for golfers who want to have precision
We liked its enhanced sweet spot, which is thanks to the Inverted Come Technology
Has a hollowed body construction expected from a muscle back
Left-hand golfers will also find their orientation
More features: Diamond Scoreline Pattern; Fluid Feel Hosel; Optimized Sole Camber
The Wilson Staff Model comes from an award-winning range of blades that pay homage to Wilson’s long tradition of forging irons. They have stunning designs and high-quality detailing. They are precision milled to offer accurate and consistent weight and characteristics, whatever the club, whatever the set. There are eight clubs in this set. They’re known for their perfectly clean topline and triple knurled hosels. Taking inspiration from the Dyna-Powered irons, the design removes unnecessary mass in their hosel and allows for a wider sole and more oversized clubhead for better playability.
Compared to the FG Tour 100, the Staff blades have a slightly more rounded radius in the soles. This helps keep the clubs off the course grass while hitting the ball precisely and consistently. However, the new Wilson 2021 line of CB irons, which are for more advanced golfers, features a Tri-Brace stabilizer for better energy transfer and incredible sound and feel. However, the Wilson Staff doesn’t have the nickel treatment on the 2021 model, which has an advanced mirror finish.
The golf iron shaft is made of a forged carbon steel face accompanied by a mass around the impact zone. Therefore, this offers a good muscle back sensation. It also has a rear cavity for greater consistency during the strike.
What do we love it for?
It has a more oversized clubhead and wider sole for better playability
Precision milled for accuracy
It has a brushed chrome finish which gives it a premium look
More features: hollow core and a low center of gravity; foam microspheres infused in a club; Tungsten Weighting; Arccos Caddie App for tracking accuracy and distance; 7 items in a set
The Cobra King forged TEC series irons look crazy for distance! However, when classic style and modern technologies merge, it results in an explosive mix. Not many muscle back irons deliver like the 2020 Cobra King Forged Tec for even more tolerance and power. The Face PwrShell technology gives the iron a forged clubhead design, and the larger sweet zone provides increased ball speeds over a wider area of the face than usual.
However, the new 5-stage forged body of the 2022 King Forged TEC offers softer sensations while ensuring distance and forgiveness thanks to its hollow cavity. But we like the hollow body of the Forged Tec, which is injected with soft foam. This, therefore, promotes the elasticity of the face for an improved rebound effect, which provides exceptional ball speeds. King Forged Tec irons have Tungsten weighting, allowing the center of gravity to be positioned with extreme precision behind the impact zone. The sensations are pure, and the tolerance increases.
The Cobra Connect helps you connect and improve your game with the help of artificial intelligence by using the Arccos Caddie App. Every King Forged TEC iron features an Arccos sensor seamlessly integrated into the handle. So, pair your set with the Arccos Caddy app to tap into golf’s richest data and make more informed decisions.
What are its best features?
We like the artificial intelligence-based Arccos accuracy tracker
An easy to use hollow iron
The Face PwrShell technology gives it a larger sweet zone
What could be improved?
It can be more forgiving
Things to Consider
Now that you know the most famous muscle back golf clubs on the market, if you still have some questions related to the characteristics of the irons, in this buying guide, we will be giving you answers to questions regarding the designs, features, and what your purchase should come with.
What Are Muscle Back Irons in Golf?
Muscle back irons, or forged blades, have a distinctive shape with a narrow top
Muscle-Backs are blades with additional reinforcement at the back of the club. This reinforcement has a double effect: it lowers the center of gravity and makes it possible to enlarge the sweet spot significantly. Some sets are said to be progressive muscle back… the reinforcement is higher in the small irons (control and precision) and higher in the long irons, making the ball easier to fly.
It has a central reinforcement which allows you to have mass next to the sweet spot
It offers a lot of control but a little less “rebound.”
They offer players more distance and feel
They offer less forgiveness
These irons are only for professional golfers
How to Pick the Best Muscle Back Irons
There are several factors that you must take into account before purchasing a muscle back golf club. From knowing the type of material they are made from, their resistance, and the types of shafts. Although, there are other extra criteria that you should analyze. Below, we will mention a few.
Individual Irons or a Set: What’s Included?
Like with most golf irons, you can purchase an individual iron or a set with the muscle back. The difference here is that you will have various lengths and designs to choose from in the bag. Also, iron sets are cheaper when you compare the price per iron. For example, a single piece of $200 iron can be sold for a thousand dollars in eight pieces. And since these irons are designed for professionals, we think you’d want more than one in your golf bag.
It wasn’t easy to find left-handed clubs until a few years ago. Right hands are the main versions. But thankfully, there are muscle backs with left-hand orientations, such as the TaylorMade SIM UDI and Cobra Golf King Tec Iron. But there are also models designed only for right-hand players. An example is the Mizuno MP-20 Golf Iron Set. So, if you’re a left-hand user, take note of the orientation the order is set in and whether your hand orientation is available before purchasing.
Every type of golf club is made from different materials. Starting with the shaft, which provides the necessary comfort, flexibility, and distance. The shaft materials are often graphite and steel. The graphite has less weight and gives you a soft hit sensation; on the other hand, the steel one gives you a more accurate impact.
The material with which the golf clubs are made conditions their flex (the ability to bend). To get clubs that reach greater height and distance, it will be necessary that the material with which they are manufactured is of less stiffness. On the other hand, if the material’s stiffness is greater, the iron will give more speed, precision, and sensitivity in each hit.
The correct length should always be determined using a biometric fitting, which takes body size and posture.
However, if you don’t want that, there is another, less precise method that may be of interest to beginners:
Measure your exact height; get a second person to help you. Measure up to date, do not use old data. Now carefully measure the distance from the beginning of the wrist down to the floor. Put on your golf shoes, relax and let your arms hang loosely. If you’re right-handed, measure the distance from your right hand to the floor – if you’re left-handed, please measure the other way around. Again, the help of a second person is crucial to get solid readings.
Now it gets a bit complicated. The determined values help to determine how much the shaft of the golf club must be shortened or lengthened (in inches). The previously measured distance between the wrist and the floor decides how much has to be shortened or lengthened.
Unlike cavity back heads, muscle back heads do not have a hollow back. This classic form of iron is usually only used by professionals, as they are not very forgiving and therefore very difficult to play.
In addition, the heads are smaller than standard club heads for hobby players. With the muscle-back iron, the entire head is solid. The ball has to be hit centrally here. Otherwise, the feel is not good. The striking distance is somewhat reduced here due to the higher center of gravity.
There are nine irons numbered from 1 to 9. The smallest number corresponds to the iron, which allows you to cover the most distance. This is already an essential element enabling you to know how to choose your golf clubs.
Also, the larger the sole is, the more tolerant it is. It optimizes contact with the ground when hitting for greater ease if rounded.
At the level of the clubhead, a wider sole lifts the ball easier and increases the tolerance of your club. Conversely, a thin sole will give you a tighter trajectory and, therefore, more precision.
For more tolerance, choose an iron with offset. This is between the shaft and the clubhead, designed to reduce unwanted slice effects.
Distance and Forgiveness
An iron with a large and wide head offers a better “sweet spot” and will therefore offer more forgiveness. As for the distance, almost all golf clubs have a number that indicates their characteristics and the distances that each one can reach, although they are usually only approximations since the final result depends on other circumstances. Below in the table, you’ll find the distances your irons can reach:
1 = 192m
5 = 155m
8 = 128m
2 = 183m
6 = 146m
9 = 119m
3 = 174m
7 = 137m
4 = 165m
Quality and Warranty
The quality of the irons are determined by their overall construction and finish. Forged irons are much more of better quality than cast irons. Although a forged iron is often expensive, it’s the best choice if you want the best quality. And we have a couple of forged irons on our list. Examples are the Mizuno MP-20 and the Cobra King Tec Iron Sets. Warranty varies from brand to brand and model to model. Callaway offers 12 months, but a model like the TaylorMade SIM UDI Irons offers two years. But take note, not all models are guaranteed.
As earlier mentioned, it’s always better to go for a set of irons than individual irons, especially if you’re a professional. This way, you’ll get a better price per piece. A good range for good muscle back iron sets is around $800 to $2000. But it’s still also possible to find a muscle back set in the list of the best irons under $500.
Lower handicap players should choose a muscle back iron or blade irons. Even though high to mid handicappers who want an incredible feel can also play with a muscle back club, they will struggle to get the needed consistency. But it’s more advisable for mid and high handicappers to choose from the best blade irons.
For consistency, it’s better to get the whole set. In addition, iron sets are cheaper when you compare the price per iron. Then, in a set, you’ll have different lengths, which will mean you’ll have the suitable iron for the distance you are shooting for.
Muscle back irons are the right pick for those who want to get that feel, feedback, and enlarged sweet spots. We’ve seen the five best muscle back irons in the market and hope you have found your best option.
With a rating of 9.9 out of 10, our Editor’s Choice and top pick is the Mizuno MP 20 HMB HMB, a Hot Metal Blade, which tells you that the iron is forged, the best quality type cannot be compared to cast irons. These irons also have the nickel-copper interlayer.
The best value-for-money model is the Callaway Golf Apex Smoke Iron. Rated 9.8, this is a tungsten-infused, multi-material construction that allows clubs to precisely position the center of gravity for better ball flight.
Finally, our best stiff shaft option is the TaylorMade SIM UDI Iron Set. The stiffness of the shaft is created to offer precision and distance. This exists in 2 versions (18° and 20°) and provides more playing comfort while maintaining accuracy.
How to Know if Your Golf Game is Ready for a Switch to Forged Irons
Are you itching to make the switch from cast to forged irons? If so, there are a number of things you should consider before making the investment.