The Milsub Before the Milsub: Part 1

When people use the phrase “Military Submariner”, it is assumed that this is shorthand for the ref. 5517 Rolex Submariner ordered by the British Ministry of Defence (MoD) and issued to divers of the Royal Navy, the Royal Marines, the Royal Engineers and British Army helicopter pilots. But the ref. 5517 wasn’t the first Submariner ever issued to these forces; in fact, it wasn’t even the second. The story of the watches that preceded the ref. 5517 in British military service is almost unknown and we would like to correct that oversight here.

Britain was the second nation — after the Italians — to use combat divers during World War II, deploying them in both reconnaissance and defensive tasks, which ranged from surveying beaches prior to amphibious landings to determine whether they could bear the weight of tanks and other heavy equipment, and mapping out enemy positions. Others were responsible for locating minefields and either disabling the mines or marking out cleared access lanes prior to amphibious landings.

Many of these tasks required accurate timekeeping and, as the few handmade Longines watches in use were hardly enough to fulfil the needs of the British forces, once the conflict was over, the Royal Navy sought a timepiece with which to equip its divers in the post-war era. Rolex had a head start, as its Oyster case was pretty much the only truly waterproof watch available at that time. And when it introduced the Submariner (ref. 6204) in 1954, the British forces ordered some for testing. However, by the time the bureaucracy had caught up with the ordering, Rolex already had a better watch, the ref. 6200, in production. This was both larger and had a heavier case with a much larger Oyster crown and tube, giving it increased depth capability to 600ft, much greater than any diver had gone previously.


Military testing took over two years in both the waters around Britain and in the Mediterranean. The watch was tested with the winder screwed down and unscrewed, and proved itself waterproof even at 400ft below the surface. But, once again, Rolex proved to be quicker than the MoD, and by the time the tests were completed and the reports filed, the ref. 6200 was no longer in production and had been replaced by the ref. 6538, fitted with the new cal. 1030. The ref. 6538 was almost identical to the ref. 6200, apart from the movement; the only change to the case was a flatter back rather than the “bubble back” seen on the earlier model. The first ref. 6538 watches had a similar Explorer-style dial to the ref. 6200.

Example of the first edition ref. 6538 with Explorer Dial
An example of a first edition ref. 6538 with Explorer Dial

After less than two years of production, the style of dial was changed to the one that is now more familiar, with luminous dots and bars.

An example of a ref. 6538 with luminous dots and bars
An example of a ref. 6538 with luminous dots and bars

Yet the ref. 6538 was not quite the settled choice for the MoD. Royal Marines divers of the Special Boat Squadron (later to become the Special Boat Service) who were issued the first watches found the bezel difficult to operate with diving gloves. Minor modifications were thus made, resulting in the A/6538, the military variant featuring a larger bezel with more pronounced ridges for easier handling; the bezel was also made from a different alloy for greater durability.

Hard Men, Hard Watch

Over a decade ago, a London watch seller I know got a call from a small watch dealer in Poole, Dorset. A beachcomber with a metal detector had found the watch buried beneath a foot or more of sand on his local beach. The watch was sent from the Poole dealer to the London one, who called me. Unbelievably the Oyster case had protected the watch from the action of the tide for over 40 years; the movement looked like new. The original glass was completely opaque as the action of the sand going over it with the tides had acted like fine sandpaper. However, the glass required only the lightest of polishes before it sparkled like new.

What is the icing on the cake is that Poole is the home base of the Special Boat Squadron — the only people to whom this very special and rare watch was ever issued.

How did the A/6538 come to being, and how was it different from the civilian ref. 6538 on which it was based?

Don’t miss Part 2 of our report on the legendary Milsub.


[Excerpted from an article by James Dowling, first published in September 2015]

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