Equipment
Three Callaway GBB Epic drivers appear on USGA Conforming Club List
Three new Callaway drivers have appeared on the USGA’s Conforming Club List: the GBB Epic, the GBB Epic Star and the GBB Epic Sub Zero.
Callaway isn’t commenting on the new Great Big Bertha (GBB) drivers at this time, so we can’t officially confirm or deny any details about the new drivers. We do anticipate that one or more of the driver models could be in play this week at the Hero World Challenge in the Bahamas, however, where they will be permitted for us. We also can point out a few things based on the USGA’s black-and-white photos.
GBB Epic
GBB Epic Star
Based on the photos, it appears the GBB Epic and GBB Epic Star are virtually identical, with the exception being the lack of an adjustable hosel on the GBB Epic Star.
Both drivers appear to use a technology called “Jailbreak,” which is highlighted on the front of the driver’s sole. The technology is rumored to connect the sole and crown of the drivers, adding reinforcement that improves energy transfer.
On the other end of the sole is a sliding weight that enables golfers to select a draw, fade or neutral trajectory bias. There are also what seem to be carbon fiber inserts on the soles of all three driver models. Carbon fiber is lighter than titanium, and its use presumably enhanced the ability of Callaway engineers to optimize the weighting of the driver heads for improved performance.
GBB Epic Sub Zero
Instead of a sliding weight track, the GBB Epic Sub Zero has two adjustable weights — one on the front of the sole, and one on the back. That reminds us of Callaway’s XR ’16 Sub Zero driver, which is the company’s current ultra-low-spin driver. It design targets better golfers, and was used in 2016 by Phil Mickelson.
The Sub Zero got its name from its center of gravity position (CG), which Callaway says is below the neutral axis line, or “sub zero.” The XR ’16 Sub Zero uses a what Callaway called a Carbon Triax Crown, an extremely thin, lightweight composite material on the top of the driver that the company said enabled its sub zero CG location.
What are GolfWRX Members saying about the new drivers? Join the discussion in our forum.
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
Aaron Rai’s winning WITB: 2026 PGA Championship
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Maria Torres WITB 2026 (June)
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...
Eric Cole WITB 2026 (June)
Driver: PXG Lightning Tour Max (9 degrees) Shaft: Project X Titan Yellow 70 TX 3-wood: TaylorMade Qi4D (15 degrees) Shaft:...
Si Woo Kim WITB 2026 (May)
Driver: Callaway Quantum Triple Diamond (8.5 degrees) Shaft: Fujikura Ventus Black 6 X Mini driver: Callaway Paradym Ai Smoke Mini...
Wyndham Clark’s winning WITB: 2026 CJ Cup Byron Nelson
Driver: TaylorMade Qi4D (10.5 degrees) Shaft: Project X Titan Yellow 60 TX 3-wood: TaylorMade Qi4D Tour (15 degrees) Shaft: Project...
westphi
Dec 4, 2016 at 12:56 pm
When is this going to be released in stores?
Red Regal
Nov 29, 2016 at 6:42 am
Callaway the new Taylor Made with so many releases.
PapaBear
Nov 29, 2016 at 2:46 am
Haven’t been this excited since the Cobra 370U was released!
KJ
Nov 28, 2016 at 9:02 pm
A lot of the comments, so true. I buy a new driver amount every 3 years. I typically buy a model that’s one year old and half the price of the original in very good shape.
erlybrd
Nov 28, 2016 at 6:27 pm
What? Looks just like 915 D4 head!!
Blade Junkie
Nov 28, 2016 at 3:31 pm
Another bottle of Snake Oil please Bartender !
B. Parsons
Nov 28, 2016 at 1:16 pm
The Korean YouTube video showed these in detail. I’m sure cally will try their best to have it pulled, but it’s still out there. Search for it on naver or another Korean search engine.
Dave R
Nov 28, 2016 at 12:21 pm
What I can’t believe it more new drivers, what will they think of next
Jordan
Nov 28, 2016 at 11:14 am
Wait, they’re coming out with an adjustable 915 driver? Color me intrigued…
Guy
Nov 28, 2016 at 11:49 am
Thats what I was thinking when I saw it.
Clay
Nov 28, 2016 at 10:30 am
I can’t believe no one has speculated that the bonded hosel design was made for Tiger. Are the “Tiger is buying TM” rumors so strong that no one wants to start a new rumor about Tiger signing with Callaway? Fine, I will start the rumor. The GBB Star is made specifically for Tiger and will not go to market. I have zero evidence but I know some people that know some people that robbed some people and they said it is true.
Michael
Nov 28, 2016 at 9:33 am
The Epic Star has my attention. Will this be a non-adjustable model that is in the $399 range? Would they want to compete with possible Fusion sales?
cgasucks
Nov 28, 2016 at 9:04 am
Jailbreak technology!??! What is that?? Does it mean if you pay someone to “unlock” it you remove the USGA COR restriction!??!
Desmond
Nov 28, 2016 at 9:23 am
You need to read the EPIC thread
Desmond
Nov 28, 2016 at 9:24 am
… or just the descriptions above. Works wonders.
Fozzie Bear
Nov 28, 2016 at 8:50 am
Oh, Mizuno Fast Track is back. 🙂
DB
Dec 2, 2016 at 12:49 am
Man, I just saw a Mizzy Fast Track at GolfMart for like $30.
If Callaway says this technology is a game changer then I’m going back to get that Mizuno tonight!