seiko divers reference

6309

Production Info

Production: 1976 - 1988
Movement: cal. 6309
Description: 150m divers

Technical Manuals

Models

Models with big cushion cases:

6309-7040 (all have big cushion cases and black bezels, though some have seen 6309-704X divers with blue-and-red bezels)
6309-7049

Models with slimmed-down case:

6309-7290 (start of the use of slimmed-down cases, black-bezel version)
6309-7290 with "17 JEWELS" on dial (Japan-made version, with black bezel)
6309-729A (identical to 6309-7290 except with blue and red bezel)
6309-729A with "17 JEWELS" on dial (Japan-made version, with blue and red bezel)
6309-729B? (very rare model, with slimmed-down case and orange dial)

Details

The 6309 divers replaced the 6105 as the standard models of 150m divers in the mid-1970s. The 6309s were marketed outside of Japan while a version using the 6306 movement was sold only in Japan (but for a relatively short 5 years).

The cal. 6309 movement is a successor of the 6105. It has 17J and runs at 21,600 bph. It's non-hacking and has a quickset day/date calendar mechanism.

Like the 6105, there are 2 series of 6309 divers. The earlier versions -- 6309-7040 and 6309-7049 -- are housed in big cushion cases and have round markers. The later versions -- 6309-7290 and 6309-729A/729B -- have slimmed-down cases and rectangular markers (which make them very similar to the current SKX007/173 models). While the earlier 6105 divers used the "turn and lock" crowns, the 6309 crowns are all screw-down. The 6309 divers have bi-directional non-locking bezels.

Some have wondered how the 6309-7049 and 6309-7040 differ. The consensus among S&C Forum collectors is that there's no difference between the 6309-7040 and 6309-7049 models. John Davis/ei8hthoms explained that the last digit of the case number indicates a regional code used for marketing (9 means N. America and 0 means elsewhere).

In the historical details provided by Mr. Tokunaga, the 6309 and its brother the 6306 were both put into production in 1976 -- the cal. 6309 movement was designed first (and serves as the base caliber for the 63 series of movements), but the 6306 diver was put into production "slightly first," before the 6309. Below is a scan of the original specification drawing for the 6309/6306 divers:

How tough are Seiko divers?

NDT34321 writes:

Another 6309-7049 torture test

I've come out of lurking mode to present my version of an extreme torture test on the 6309-7049 150mm diver... this watch spent over 1100 hours underwater...I was a contract diver who worn the Sekio as a good luck piece....not a part of my working system....I had made a 4" rubber band cover out of a leg tourniquet to fit over the watch...pipelay barge or dredge or jet barge divers and Non Destructive Testng divers don't wear watches....strange?...Not really..the limited visiablity conditions where my type of diving takes place were river bottoms and mid harbors(the sekio was there)in 76 Boston Harbor USA had 12' of overburden above harbor floor(the 6309 was there)...biopsy (coreing sampling) a bridge spanning the Mississippi.. easy current.. no visibility (the sekio was there)torque valve on the hydraulic machine slammed my wrist into a piling...(the seiko was there)I add that I did wear a 50cm depth gauge at all times..the incident broke a bone in my wrist it moved the bezel to one side..new bezel and crystal... the watch was find... destroyed my GG..the Seiko had 5 years of this real time torture test... I also played in my Sekio..this was a 24hr watch...the watch has been restored now by IWW... Jack related not a spect of rust on the movement... it is still my everyday watch though its diving days are over...so when a watch is nominated as one of the most robust and enduring divers... with a strong record to prove by....I believe my unintentional real life torture test on my 6309 speaks well of the watch.

The 6309 divers, like the 6105s before them, were extremely popular among the military. Here is an anecdote below ("17 Year Long Torture Test, Seiko 6309."):

I found this on the Equation of Time dive board. I found it very interesting.

17 Year Long Torture Test, Seiko 6309

Posted By: Andy

Date: Friday, 1 February 2002, at 7:51 p.m.

Gents

I thought you find the following interesting as to how much punishment my Seiko 6309 diver has taken as a military watch.

Purchased 1985 in Germany at the PX.

Patrolled the streets of Nurnburg Germany on the wrist of a Military Policeman involved in multitudes of bar fights and assorted rough play.

1987 it moved to Puerto Rico as a Military Police Investigator's watch and held up through more rough play and off duty diving.

1991-1997 it survived airborne school, 50 plus additional jumps, water insertions in Panama and combat as part of the infamous Task Force Ranger in Somalia in 1993.

1997-present it is still serving me well as a daily watch in the U.S. Border Patrol patrolling on motorcycles and quadrunners daily.

All this with only one rebuild and a replacement bezel ring that was knocked off in a bar fight.

Seiko "Celebrity Sightings"

Ed Harris wore a 6309-704x in the 1989 movie "The Abyss":

In this 1983 photo, Mick Jagger is wearing a 6309-704x: