Vintage 1970's Heuer Montreal 110.503 NC Cal 12 Automatic Stefan Bellof NSA

The history of the Calibre 11

Starts at the end of 1965. As Büren had pioneered the production of micro-rotor movements, Gérald Dubois (of Dépraz & Co., a chronograph specialist) figured out that these would be thin enough to be the base for a modular chronograph movement. Dubois contacts Hans Kocher of Büren Watch Co. SA. In need of commercial partners, they manage to convince first Jack Heuer and then Willy Breitling to support the project. On February 2nd, 1966, an agreement is signed. The four-party Chronomatic consortium is born, including two rival brands teaming up to develop their own automatic chronograph. For confidentiality purposes, the development is code-named Project 99.

 The convention signed on February 2, 1966, between Dépraz & Co., Heuer-Léonidas SA and Léon Breitling SA. The partners asked Büren Watch Co. to build the blanks and the automatic movement of an automatic chronograph, the basic execution of which is designated by calibre No. 111. They have an exclusive right to use this calibre. They plan to have Dépraz develop and manufacture the chronograph mechanism to equip this calibre.

Büren is in charge of the base calibre. Dépraz of the chronograph mechanism. Three brands – Heuer, Breitling and Hamilton (who acquired Buren during the development process) – will fit the movement inside their watches. A patent application for the Calibre 11 is filed in September 1967. At the end of 1968, about 100 pre-production movements are assembled in prevision of the 1969 Basel fair. On March 3rd 1969, the movement is officially presented, simultaneously in New York and Geneva. A month later, the three brands present their first chronographs at the 1969 Basel fair. With the practicality and comfort of automatic winding, the chronograph becomes a staple of motorsport… the Calibre 11 is used to power iconic watches by Heuer (Carrera, Monaco, Autavia), Breitling (Chrono-Matic) and Hamilton (Fontainebleau). And later by other brands such as Bulova, Kelek, Zodiac, Elgin, Stowa…

So, who won the race?

Zenith’s automatic chronograph was the first to be unveiled to the world. It was presented during a press conference in January 1969 and christened El Primero (“the first” in Spanish). The reality is a bit more complex. There are endless debates about which was the first automatic chronograph, as both the Seiko and the Chronomatic movements were announced later the same year. What’s more, El Primero was not the first to hit the market. But the controversy about who came first doesn’t really matter anymore… what is important is the impact that these movements had on watchmaking history. Since then, the automatic chronograph has remained one of the most popular complications.

THE CALIBRE 11

The Calibre 11 is a 17-jewel modular chronograph measuring 31mm x 7.7mm. This modular architecture implies first a base movement, a micro-rotor automatic calibre made by Büren, in charge of the timekeeping part. Beating at 19,800 vibrations per hour, it boasted 42 hours of power reserve. Manufactured by Dépraz, the lever chronograph module is assembled on the backside of the base movement. This movement has a bi-compax display, with a 30-minute counter at 3 o’clock and a 12-hour counter at 9 o’clock – no running seconds sub-dial. The date is indicated at 6 o’clock. The unusual crown position, at 9 o’clock at the opposite of the chronograph pushers, is a signature feature of the movement.

THE CALIBRE 11 AND ITS EVOLUTIONS

Like most movements, the Calibre 11 has been optimized several times over its lifetime. As early as 1969, a barrel spring providing less torque is used. The date jump mechanism is adapted. The sliding pinion is changed and made in steel.

 In 1971, a variant running at 21,600 vibrations per hour and named Calibre 12 is introduced. It becomes the main product of the calibre family. It uses a stronger barrel spring. The gear train and balance wheel are adapted. The chronograph hammer is modified to improve shock-resistance.

Heuer Montreal

This model fit the Heuer strategy of expansion to the North American market. 1976 the Olympic Games took place in Montreal, the second largest French speaking city in the world. Formula One racing has also hosted a race in Montreal every year since 1978. The Canadian Grand Prix takes place on the Circuit Gilles Villeneuve. The new model line won over consumers with a totally new, modern and almost rectangular design. This model series remained in the portfolio until the end of the 1970’s and emphasized its role as a design innovation.

The young promising German Formula One racing driver Stefan Bellof was frequently seen wearing a Heuer Montreal belonging his father. His accidental death on the racetrack in Spa on 1st of September 1985 shocked the motor sport world. His Heuer Montreal is on display in Stefan-Bellof-Memorial nearby Gießen, Germany.

This is a beautiful Heuer Montreal from the 1970's Reference number 110.503. It is very rare to find a watch this old with Heuer Service box. Defiantly a collector watch. Please look at all the pictures, as they are part of the description. The watch is working and Keeping great time This is a highly collectible watch. Very few left with this rare movement. Sure, to increase in value overtime, and a great addition to your collection. The condition of the watch is the same as it appears in the photos.   The watch is working and is part of our new Certified Pre-Owned CPO Program.  Contact me if you have any questions first.