The introduction of screw down pushers and a larger winding crown in the mid 1960’s changed both the aspect the status of the Rolex Cosmograph: although is still had the same diameter, the watch appeared bigger and more rugged. The mention Oyster on the dial was an additional part of pure Rolex DNA put into the watch.
1971 edition of the “24 hours of Daytona”
The first Cosmograph with screw down pushers was introduced in 1965 with reference 6240 powered by cal. 722 and its production continued until 1969. For this model, the mention Oyster reappeared on the dial of a chronograph: previously, it was only used on older chronographs with pump pushers to distinguish them from the models with square pushers.
Cosmograph ref. 6240 with tropical dial (Photo O&M)
The qualification Oyster – that guaranteed improved water resistance – was due to the presence of screw down pushers as well as a 7mm winding crown from the 700 series (instead of the 6mm from the 600 series mounted the Cosmographs with pump pushers). The pushers used for the reference 6240 are often referred to as the “prototype pushers” or the “fat pushers”; they will be used until the early 1970’s on the references 6263 and 6265.
Fat screw-down pushers for ref. 6240 and early ref. 6263/6265
The reference 6240 was mainly available with a black bakelite bezel, but according to M. Pisani it is quite probable that Rolex produced the first examples (1965/67) with a metal bezel also.
There is a debate among collectors to determine if the first 6240’s could have been issued without the mention Oyster on the dial. Some people admit it for very early examples and some others don’t want to hear about it. Here’s a one owner 6240 with a 1,29 million serial number, a 6239 caseback and a 72B movement: the dial does not carry the word Oyster…
Early Cosmograph ref. 6240
The production of the final version of the manual wound Cosmograph started in 1971 with the references 6263 and 6265, powered by cal. 727 (21,600 bph) and with a case featuring screw down pushers. The production stopped in 1978, but the most recent examples have cases with a number of over 9 digits (1986 to 1987) because the cases where only numbered at the moment the watch went into circulation.
Early 1970’s Cosmograph ref,Replica TAG Heuer – CARRERA Heritage Calibre 6 WAS2151.BD0734 Men Watch. 6265 with white “ s” dial and “,Omega Speedmaster 3220.127.116.11.01.003 Watch;fat” pushers (Photo A. Shear)
The only difference between the two references is the bezel: bakelite for the 6263 and stainless steel for the 6265.
Cosmograph ref. 6263 with white “ s” dial and service pushers (Photo A,replica dior viii cd124be3c002 watch. Shear)
As for the dials, they were either black matt or satin-finish silvered. For the gold watches, they were black or champagne with matt finishing.
Late 1970’s Cosmograph ref. 6263 with black dial and red Daytona (Photo A. Shear)
In spite of these improvements, the Cosmograph never became a great seller. In the mid1980’s, Rolex decided that it was time to “upgrade” the watch to the “level” of the other toolwatches of the brand, that had bigger cases and sapphire crystals.
Booklet for the Cosmograph ref. 6263
Early 1970’s race on the Daytona Speedway
Acknowledgements: M. Pisani
For Jeff’s original post in Rolex forum, please CLICK HERE