Omega Speedmaster Professional Calibre 3861

The Omega Speedmaster Professional has been a standout value proposition for the longest time.  It has everything a brand would kill for – pedigree, a compelling history, a steadfast fanbase and a Bang-For-Your-Buck price tag.  For a halo product, its BFYB quotient simply improved with every price increase of its competitors.  It came to a point where the steel Rolex Daytona had a recommended retail price that was almost twice that of the pre-2021 Speedmaster Professional’s.  The Calibre 3861, then, could not have come at a better time.

Photography by Ronald Chew

by The Balance Coq

  • January 9, 2024

Outside of Speedmaster anoraks, it is unlikely that most people could tell the difference between a pre-2021 (3570.50) and a 2021 Speedmaster Professional.  And there is good reason for that.  As it is Omega’s halo product, there was no chance Biel was going to go down the revolutionary path with the Speedmaster Professional redesign.  And yet, at the same time, almost every single element of the Speedmaster Professional is new in the 2021 version.  We are talking a new case, bezel, pushers, crown, dial, hand-set, caseback, clasp and bracelet.  A brand new watch, painstakingly made to resemble its predecessor.

The Calibre 3861 Movement

With this Calibre 3861, Biel finally brings the Speedmaster Professional up to speed with the rest of its Omega stablemates. The Calibre 1861 movement was launched in 1996, which meant that the little manual cam-operated chronograph movement was in service for a lot longer than it should have.  Well, it is not actually “new” new.  It was first seen in the steel and gold versions of the 2019 Speedmaster Apollo 50th Anniversary, as well as the blue Snoopy Moonwatch.

Calibre 3861 has a whole host of improvements over the much venerated Calibre 1861.  The new movement is comparatively more shock resistant, more resistant to magnetism (Ronald: does that make it …less attractive?)  and has a co-axial escapement, a silicon Si14 balance spring, and a longer power reserve.  Being Master Chronometer-certified, the mechanical manual winding movement reportedly runs 0/+5 seconds per day.  The winding action is now smoother and feels less strenuous to wind, although you will be turning the crown a wee bit more on account of the longer power reserve.  Speaking of the crown, it is more than a touch larger, allowing for a better winding experience.

We are not sure who needs to hear this, but the new movement also (finally!) has hacking seconds.

The dial

The overriding theme to the new Speedmaster Professional’s redesigned dial must be vintage homage.

For instance, step-dials are now back in, after some 46 years of flat dials.  The step dials certainly lend the chapter ring some extra depth.  Some earlier examples of the new Moonwatch had concentric circles in the sub-dials.  The later ones, like the one here in this Pictorial, have to settle for plain sub-dials.

The tracks and markers have been “corrected”.  The chronograph track at the periphery now has 3 divisions per second, which is relevant considering the 3Hz frequency of the movement.  Moonwatches with 861/1861 movements had dial markings mismatched to their calibers (3Hz movement, 2.5/5Hz dial), and this redesign sets it right.

For the pedants, there’s a slight change in the size of the Omega symbol and wording alignment on the dials.  The Hesalite version has a printed logo, whilst Omega put in extra effort to apply the diamond-polished logo on the sapphire sandwich version.

The new hand set pays homage to the Reference ST105.012 Speedmaster Professional; the now-thinner central seconds hand has a slightly larger diamond luminous tip that is positioned closer to the periphery of the dial. The tear-drop counterweight makes a triumphant return.  The hour and minute hands are probably the only two parts carried over intact from the Reference 3750.50.

TBC is happy to report that lumination is fantastic on the new model, and keeps glowing for a considerable amount of time after a little time under the sun.

The bracelet

Omega did not just put in a new improved movement and call it day.  The bracelet and clasp of the 2021 Speedmaster Professional have also received substantial improvements.

The bracelet off the 3750.50 Speedmaster Professional has no easy adjustments, and is chunky with its 20mm/18mm tapering (but nothing like the SMP Seamaster bracelets that do not taper at all).  The new Speedmaster Professional has been fitted with a flatter bracelet with a 20mm/15mm taper.  The narrower end of the bracelet also means is that the new clasp that houses the on-the-fly micro-adjustment is also literally half the size of anything a class-leading modern Rolex has.  The new 5-link bracelet has a narrower centre link, replete with smaller links that would allow for a more precise fit, not to mention a more comfortable wearing experience.

Omega has also engineered some product differentiation in the bracelets of the Hesalite and sapphire twins.  The bracelet on the Hesalite version of the new Speedmaster Professional is completely brushed, whereas the one on the Sapphire sandwich version has polished interlinks.

The most important bit

All the changes listed are good and all, but the most important improvement is that Omega, in all its wisdom, decided to put the dot back over the 90.

Bottom line

Omega brought the Moonwatch into the 2020s with the Calibre 3861, while simultaneously walking back some design decisions to bring the new reference closer to 1960s’ reference ST105.102.  Which should, no doubt, please many Speedmaster Professional owners.  Of course, there are die-hards who insist that it was wholly unnecessary to discontinue the Calibre 1861 series.  After all, they would like to point out, the Calibre 861/1861 has logged many hours in space exploration and had actually passed the NASA endurance tests. The new movement has yet to accomplish this.

Whatever the case may be, the Calibre 3861 Speedmaster Professional acquits itself with a long list of thoughtful and timely improvements over its predecessor.  The stepped dial, upgraded power reserve, METAS certification, reshaped case profile, vintage-inspired and extremely comfortable bracelet, bigger crown, and shorter “tear drop” counter weight to the chronograph seconds hand are all noticeable updates. It is a very respectable continuation of the icon that is the Moonwatch.  You won’t be getting the 1861’s latter-year “big box” presentation, but really, your only dilemma as a potential owner is this: Hesalite for history’s sake, or the sapphire sandwich, with a window to that beautiful movement?


ModelSpeedmaster Professional
Case MaterialStainless steel
Case Diameter42mm
Case Height13.2mm
Lug Width20mm
MovementCalibre 3861 mechanical manual winding
WearsTrue to size

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