Review: 6B MKIII Scramble Chronograph

Late last year, long-time Worn & Wound reader James Smith (you Instagram fanatics may better know him as thejames80) reviewed his fantastic Seiko ref. SPB053 in a guest post for the site. Today, he’s taking a close look at another watch from his collection; it’s a unique, limited piece, and it’s from a brand you likely have never heard of—the MKIII Scramble from 6B.

Spend enough time in the watch world and you are sure to come across the custom strap maker GasGasBones, aka Carl Evans. If the look of these unique and fully customizable straps do not stick with you, the name surely will (I know both lingered with me when I discovered the brand years ago). While the straps are deserving of a full review in their own right, I am here to take a look at the MKIII Scramble offered by Carl’s lesser-known brand, 6B.

Like GasGasBones, 6B is a one-man operation run by Carl himself. The name 6B is derived from the Ministry of Defense (MOD) historical code for the Royal Air Force (RAF), from which Carl retired after a 25-year career. The 6B code (sometimes 6BB or 6A or 6E) was stamped into the case backs of military issued watches. For more information on these specific military watches, check out Time Spec: 1970s British Military Asymmetrical Chronographs and Time Spec: A Primer on Military Watches.

The MKIII Scramble is the third offering from 6B. Like the prior two, this is a limited edition release and it comes with incredible custom packaging (more on that later). There are quite a few things that set this watch apart from other similar military-styled chronographs, so let’s jump right to the review.

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Review: 6B MKIII Scramble Chronograph

CaseStainless steelMovementValjoux 7750DialMatte BlackLumeC1-GL Super-LumiNovaLensSapphire with double ARStrapTwo nylon mil-strapsWater Resistance50 metersDimensions38mm x 45mmThickness13.5mmLug Width18mmCrownPush/pullWarrantyYes—1 yearPrice$2250

In military aviation, scrambling is the act of quickly getting military aircraft airborne to react to an immediate threat, usually to intercept hostile aircraft.


The case measures 38 millimeters in diameter with a lug-to-lug dimension of 45 millimeters, and the drilled lugs are 18 millimeters wide. The thickness is 13.5 millimeters, which makes this one of the thinner Valjoux 7750-based chronographs that I have come across.

The mid-case is fully polished and has a relatively simple, classic case shape with slab sides. The standout feature of the case is the bezel. The fixed bezel is finely brushed with a sunburst finish. The top and bottom edges of this brushed band are bordered by narrow, polished strips, and this mix of polished and brushed surfaces plays with the light in pleasant way. Also, the bezel area slopes up from the mid-case to the slightly domed crystal and makes for a snag-free case. The sapphire crystal features anti-reflective coating applied to both sides, and it’s effective in keeping away reflections while having a slight purple hue to it in certain lighting.The crown (measuring 6 millimeters by 3 millimeters) is unsigned and does not screw down, which seems appropriate for a pilot’s watch with 50 meters of water resistance. Signing the crown with the 6B arrow symbol would have been a nice (and somewhat expected) touch, but this crown is sterile.

Flipping the watch over is a display case back, which shows the undecorated Valjoux 7750 (also a small point of contention, as some decoration would have been welcome here). Previously available, but now sold out, some Scramble watches had a solid case back with an inscription that read, “DON’T COME AND TELL – RING THIS LIKE HELL!” with “SCRAMBLE” over an image of a scramble bell.

Carl describes the inspiration on his website:

“While looking at some old Pathe war time footage of the Battle of Britain, I came across a clip of a chap frantically ringing a scramble bell like crazy and all the aircrew running for their aircraft.”

This case back version plays nicely into the watch’s name, as the term “scramble” was first used during the Battle of Britain. The display case back on the watch reviewed here contains minimal branding and shows the dates of the Battle of Britain, which spanned July 10, 1940 to October 31, 1940.



One of my favorite aspects of the MKIII Scramble is the matte black dial with stark white hands and dial markings. The dial has printed lume-dots for the hours (absent at 3, 6, and 9) and unlumed minute marks around the perimeter. At the very edge of the dial, a perimeter line rings the dial and runs through the minute marks. Lines run from the hour indices toward the center of the dial and connect to an inner circle. This inner circle is only interrupted by the chronograph’s sub-dials, and it’s similar to a dual function gauge found within aircraft instrument panels. Overall, it’s a pleasing aesthetic and it kind of reminds me of something celestial, like a constellation.

All the sub-dials have a circular machined finish, which creates some depth to the dial. The running seconds sub-dial has only hash marks at the 5-second marks, while the chronograph sub-dials have Arabic numbers to distinguish them and to aid in reading the elapsed time.

The pilot’s hands are lumed and legible. Both the primary minute hand and the chronograph second hand are angled toward the dial, and at their ends they curve down. I imagine that this slanting helps the hands fit under the domed crystal while also keeping the overall case thickness to a minimum. Plus, it’s a nice, vintage-inspired touch.

C1 Super-LumiNova paint is applied to both the dial and hands. While C1 is not particularly strong here (or in general), the stark-white daytime color is what gives the dial its signature, high-contrast look.


Inside the watch, the Valjoux 7750 automatic chronograph movement ticks away at 28,000 bph, and my particular example has been keeping excellent time while on the wrist. This 25-jeweled, integrated caliber hacks and can be manually-wound, and it boasts a 44-hour power reserve. The pushers activate and reset with a nice click that is typical of the 7750. For more information on this movement and its history, see Chronography 5: The Valjoux 7750.

Straps and Packaging

The MKIII Scramble ships in a custom wooden “ammo” box, and this packaging is just over the top! Removing the lid off the box and you are greeted with a Spitfire aircraft instrument panel cluster with the dial of the Scramble showing through a cut out in the panel. The underside of the lid contains time setting instructions, a warranty date, and a sketch of the Spitfire, which was a commonly used RAF fighter aircraft from WWII. Also included in the packaging is a key with a custom message on the key holder. The key is inserted into the instrument panel and is used to lift the panel from over the lower packaging area. The lower packaging area contains the Scramble watch head, two nylon straps, a spring bar tool, and a single slot leather wallet.


Of the provided straps, one is a MOD-standard grey Phoenix G10 strap. The second strap is a custom mil-style strap from GasGasBones and comes in an olive color. It has a combination of a metal lower keeper and a fabric upper keeper. The fabric is soft and flexible straight out the box. This strap also has “MKIII” laser-etched on the buckle, which is a nice touch.

The wallet is an uncommon item to receive with a watch, but it’s a nice addition to the packaging. One side of the wallet depicts the firing order of the Rolls Royce V12 Merlin aero engine which powered the Spitfire aircraft. The other side has the 6B logo and additional engravings can be customized on this side by request. The custom spring bar tool also doubles as the container for the spring bars—just unscrew the spring tip from the base and shake out the provided spring bars. The far side of the spring bar tool is signed with the 6B arrow symbol.


On the wrist, the Scramble is a well-fitting and comfortable, smaller-sized chronograph. I particularly like the dial design (date free!) and unique bezel style. To me, this is a modern execution of a pilot’s watch with some historic design cues, but overall the watch doesn’t feel derivative. Given the design and the history poured into the packaging, I can imagine the watch being worn by a present-day pilot (preparing to scramble a fighter jet, no doubt) on one of the provided nylon bands.During my short time of ownership, I have fitted several leather straps onto the watch, including some simple leather two-piece bands and a Di-Modell Chronomisso strap. As you would expect, the vibe changes with the strap you put on the watch.

The pricing seems in line for a limited production modern chronograph with great finishing and unique packaging. As of this writing, of the 50 MKIII Scrambles producesd the number of watches remaining is down to the single digits. In speaking with Carl, these are produced in small batches and the final watches are currently being assembled. So if this one catches your interest, you might want to act fast. 6B

Photography by James Smith

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