The Seiko 6139 automatic chronograph – a historical movement in its own right, like this full serviced 1970 Seiko 6139-7010 SpeedTimer "Military" chronograph, with Arabic dial, here – was one of the first automatic chronographs created and ranks with Zenith’s El Primero and Heuer’s Calibre 11.
The best thing about these made in Japan-only Seiko 6139-7010's? They feature atypical Arabic numberals counting the hours - Seiko used this designed sparingly during this era, and it gives the watch a great military stance.
And it appeared the Japanese military, in the form of the Japanese Defense Forces, agreed - these were issued to the JDF navy (JMSDF) and air (JASDF) forces; issued examples are exceedingly rare, and feature military insignia on the case back and JDF in Kanji Japanese. A 1981 Japanese TV special, "The Last Show," highlighted JASDF pilots and their U.S.-provided F-86 Sabre and Mitsubishi T-2 fighter jets - and on the wrist? The Seiko 6139-701x, naturally.
Back in the 1970’s, Heuer and Zenith had taken hold of the entire sports watch industry by racing to become the first to produce an automatic chronograph. It has been widely debated who won, but in the background of this skirmish, Seiko quietly created one theirs at the same time, beating the Swiss at their own game – the Seiko Ref. 6139.
During the early months of 1969, Seiko put the final touches on its revolutionary 6139 chronograph - in fact, the Japanese company first began putting the 6139 in automatic chronographs as early as January of the same year.
Seiko published its first advertisement for their new automatic 6139 chronograph in February 1969, easily beating the Swiss - however, the company was concentrating on the release of the world's first quartz watch, the Astron, which would completely disrupt the watch world as it was known at the time (again, much to the chagrin of the Swiss watch industry, we're certain). We possess 6139 dials dating back to October 1968, indicating Seiko beat all other rivals to produce the world's first automatic chronograph. Period.
The 6139 was the first chronograph to have a vertical clutch, a feature considered to be one of the hallmarks of a superior automatic chronograph movement. The 6139 features an automatic column wheel timing control and an integrated chronograph, which means the entire movement was designed and built to be a chronograph, vice being an automatic movement with a mere timing module.
This Seiko 6139 "Military" comes on a vintage stainless-steel Seiko bracelet, and with nylon strap, rugged travel case, and springbar tool.
1970 Seiko 6139-7010 SpeedTimer "Military" JDM Automatic Chronograph
DIAL: Brilliant black Arabic dial in great condition; matching minute and hour hands, with vibrant red chronograph hands on main and subdial. Day/date – with Kanji Japanese/English variants – at 3 o’clock position, and with lume plots that shine.
CASE: Stainless-steel case measures 41mm x 44mm, with no evidence of machine polishing.
CRYSTAL: Correct Seiko Hardlex crystal, no scratches, cracks, or imperfections.
BAND: This Seiko 6139 Military comes on a vintage stainless-steel Seiko-signed bracelet, which will fit up to an approx. 7.5 inch wrist - although not original to this watch, it matches well. This chronograph also comes with a black nylon strap.
MOVEMENT: Seiko 17-jewel 6139A automatic movement, manufactured in July 1970.
CROWN: Recessed unsigned stainless-steel crown.
CHRONOGRAPH PUSHERS: Chronograph pushers depress with satisfying click – no sticking - and the red chronograph main and subdial hands reset as designed to zero.