Equipment
Charl Schwartzel’s drilled-out Miura irons: A builder’s perspective
We see plenty of cavity back irons on the PGA Tour. Most of these irons have been strategically designed to position weight and center of gravity to maximize performance. Spotted this week at the AT&T Pebble Beach Pro-Am: a nonconventional set of “cavity backs” in the form of Charl Schwartzel’s drilled-out Miura MB-001 blade irons.
As first reported by Golf.com’s Andrew Tursky, Charl, an equipment free-agent, bought the irons online, and after tinkering with them (obviously, Charl is a true gear nut), he felt the irons were just a bit too heavy at D6 swing weight and wanted to bring them down to around D3. These number will seem quite arbitrary to some, so to help explain swing weight, we have a short video below
Now, the question comes down to why would he drill out the irons instead of just having the clubs built to his desired spec?
In the case of Miura irons, a company founded in Japan. The iron head weights are heavier than others on the market because Japan spec irons are generally built to shorter lengths than their North American counterparts. The clubheads are noticeably heavier in the shorter irons and wedges (see chart below), which is why we see more holes in the pitching wedge vs. the longer irons.
Since the MB-001’s are a solid muscle design with no badges or weight ports in the head, there is no other way to remove the mass needed to hit a lighter swing weight for Charl—unless Miura was to produce a set heads at a lighter weights by grinding off mass during the final production steps before final finishing.
Head weight specs 3-PW starting at 245g at the 3-iron.
As a result, when built with heavier tour weight shafts (anything 110g or above) and at a standard North American length (37″ – 7 iron, or longer), the clubs will end up being heavier than what would be considered standard swing weight (usually between D1-D4). Let me please point out that in the golf club manufacturing world there are very few standard practices or measurements beyond the USGA ruler and swing weight scale. Although the phrase “standard clubs” is still common nomenclature, it applies very little to the custom club building world.
Beyond adding mass to the grip end of the club to counteract the heavier weight of the heads, a practice known as counterbalancing, the only other option is to drill mass out of the clubhead (see full video above for further explanation). Charl reportedly did the drilling himself when fine-tuning the clubs and after a few holes got them right where he likes them.
Based on the thickness of the iron muscle and the amount of mass removed from each head (roughly six grams), these holes have no effect on the performance of the irons (but have probably killed any potential resale value on the open market—bearing in mind that last part is tongue in cheek). If Charl wins another major with these, who knows what they would be worth.
Other examples
This process of drilling out mass has also been referred to as “porting,” and club builders have been doing it for a long time. In the case of wedges, porting not only helps reduce clubhead weight, but can also help (in a very, very small way) remove mass from lower in the head to raise the CG. It’s the exact reason Callaway introduced this design feature in the original PM Grind and continues with the design philosophy today in the JAWS MD5.
With Bryson’s wedges being more than 1″ over standard length, weight had to be removed from the head.
We don’t recommend you start drilling holes in your irons and wedges just yet and suggest seeing a professional club builder to help you sort out your specs and get you dialed in. For more pictures of the clubs Charl Schwartzel is using this week, head to the GolfWRX forum: Charl Schwartzel – WITB 2020 AT&T Pebble Beach
Neal Shipley was the first to admit that he enjoyed his food while in college. But since his days at Ohio State, he’s slimmed down and earned a PGA Tour Card.
That hasn’t stopped him from having fun with his wedge stampings, though it’s led to some misunderstandings.
On the 54 (degree), we have ‘Big Fudge,'” Shipley told GolfWRX. “It was supposed to be ‘Big Fridge,’ so this happened a little while ago. ‘Big Fridge’ was a nickname between my college teammates and I, with ‘fridge’ meaning stomach, a big stomach.
“We told the Ping guys to put … ‘Big Fridge’ on it, and I think maybe some bad cell service or something, and they thought I said ‘fudge,’ so they put fudge on it.”
On Shipley’s 50-degree he also continues the food theme, this time with his go-to order at the “Golden Arches,” and his stamping “DONS 7.”
“The number 7 meal, the two cheeseburger meal, that was my McDonald’s order, back when I would have McDonald’s frequently,” Shipley shared.
At GolfWRX, we are a community of like-minded individuals who all experience and express our enjoyment of the game in many ways.
It’s that sense of community that drives day-to-day interactions in the forums on topics that range from best driver to what marker you use to mark your ball. It even allows us to share another thing we all love – buying and selling equipment.
Currently, in our GolfWRX buy/sell/trade (BST) forum, @raw10628 has a L.A.B. DF3 putter and Masters putter cover up for grabs.
From the listing: “Some great items here today, time to thin out and make room for next set of gear. All prices include shipping.
LAB DF3 Purple 33.5” 68° lie with TPT – $725. LAB Masters release DF3 cover – $150.”
To check out the full listing in our BST forum, head through the link. If you are curious about the rules to participate in the BST Forum, you can learn more here: GolfWRX BST Rules
Driver: Ping G440 LST (9 degrees)
Shaft: Accra TourZ Green 5-M4
3-wood: Ping G440 Max (15 degrees)
Shaft: Accra TourZ Green 6-M4
5-wood: Ping G440 Max (19 degrees @18)
Shaft: Accra TourZ Green 6-M4
Hybrid: Ping G440 (23 degrees)
Shaft: Oban Isawa Red Hybrid Shaft 04 Flex 70 Gms
Irons: Srixon ZXi7 (5-P)
Shafts: Aerotech SteelFiber Private Reserve i80
Wedges: Cleveland RTZ (50-MID, 54-FULL, 58-MID)
Shafts: Aerotech SteelFiber Private Reserve i105
Putter: L.A.B. Golf OZ.1i
Shaft: ACCRA Putter Shaft
Grips: Golf Pride Tour Velvet
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craig adams
Mar 12, 2020 at 12:42 am
Charles golf game has holes in it. He’s out of the top 200? A golfer as talented as he is shouldn’t have to tinker with clubs. Manufacturers should be throwing their clubs at him. Did his game go sour since moving to PXG? Why do golfers change a winning combination? Look at Westwood and Jiminez; been playing with Pings all their career.
Eldrick
Feb 20, 2020 at 3:38 am
Looks like his Gapr low is a glued non adjustable one.
Nack Jicklaus
Feb 12, 2020 at 1:02 am
He should have just drilled all the way through the faces like the old “Hammer” driver. Boom!!!!!!!!!!
Ima Fitter
Feb 10, 2020 at 5:02 pm
Love it! You don’t need to spend a ton of money on a new set of irons. As long as they are forged and you like the appearance, pre-owned irons can be fit to your swing. Change the loft & lie, change the shaft, change the grips…any qualified club builder can make them work for you.
Benny
Feb 8, 2020 at 8:02 pm
Great catch Wrx and article. Charl left PXG a while ago. But truly suprised he couldn’t get a set directly and have them custom grinded. Anyways great details and love the comments fellas.
bob stelben
Feb 8, 2020 at 3:01 am
Good video on swing weights. Can you explain tipping of the shaft and the reasons or advantages/disadvantages?
Steve
Feb 7, 2020 at 3:23 pm
I thought Schwartzel was a PXG guy? Guess I am mixing up who Parson’s friends are. And I agree….drilling holes in Miura irons is like adding your own touch up paint to the Mona Lisa. To each his own, I guess.
Funkaholic
Feb 7, 2020 at 4:55 pm
I doubt a pro is bagging those Miuras for status, he is going to play the grooves off of those babies, appearance is for weekend hackers.
Donn Rutkoff
Feb 6, 2020 at 3:17 pm
Palmer probably drilled out hundreds of clubs. Tinkering was common. To suit your own swing.
Fergie
Feb 6, 2020 at 12:33 pm
Drilling Miuras like that is, well, blasphemy. He should just get it over with and get CB’s.
Funkaholic
Feb 7, 2020 at 4:53 pm
CB’s are not the same idea at all, he is reducing swing weight, a CB redistributes weigh to lower in the head making raising MOI and them easier to launch.
Mike Cleland
Feb 6, 2020 at 10:32 am
I grew up playing D5 S/W clubs with standard lengths. Does any manufacturers make heavy headed clubs or do they just shove weight down the shaft & change the center of gravity. All my clubs are covered with lead tape. Any suggestions?
PS: I really enjoy your blogs
jgpl001
Feb 6, 2020 at 3:50 am
Nasty workmanship on a quality blade
He appears to be missing the drilled effect of hs old pig’s……
Dennis
Feb 6, 2020 at 1:28 am
Do all the pros go for swingweight instead of MOI-Matching?
Gurn
Feb 6, 2020 at 12:19 am
Those Miuras need that treatment like a hole in the head
bill bourne
Feb 5, 2020 at 8:01 pm
Does drilling out the backs affect the overall thickness spec?
JP
Feb 6, 2020 at 8:32 am
Huh? Overall thickness spec? What is that?
Tim Armington
Feb 7, 2020 at 7:54 am
You dont know what a thickness spec is??? Wow.
Funkaholic
Feb 7, 2020 at 4:56 pm
Ha! This guy doesn’t know what thickness spec is!
maroon
Feb 8, 2020 at 4:32 am
I know but it has nothing to do with golf 😉