Not a military watch per se, as it was beaten to the '79 Bund contracts by Orfina unfortunately, but a game attempt by Helmut Sinn to get it nonetheless. Using a case very similar to the Heuer Bund (not the same, as shown by 'Sweets' in his comparison) and identical bezel but using the automatic L5100 (the same movement in the contract winning Orfina) seemed to be logical, and he'd had plenty of experience with the Heuers as he serviced the issued watches on behalf of Heuer, however it wasn't to be.
Produced between 1981 and 2003, there were three main variations, the first had no 24hr dial at 12 o'clock, the second included the 24hr subdial and the third changed to a conventional caseback instead of the 4-screw retained system used by the first two incarnations which was, again, the same as the Heuer system.
During its 22 year life, there were many minor variations; flat crown/Sinn crown, orange chrono hands/red chrono hands, in-filled lume/complete lume main hands, 1/5th sec markers/1/4 sec markers, 'MILITARY' script/no script etc, so it can be confusing, especially as some will be well into their second or third service by now which only confuses things with service replacement parts.
Anyway, the first generation of the 156 is one of the scarcer of the range, generally considered to be powered by the Lemania 5012 variation of the 5100 due to its missing 24hr subdial - however this may not be true, as missing 24hr dials do not necessarily equate to a 5012 varient, as Chuck Maddox, Pascal S, Sweets and company can testify. After listening to it, I lean heavily towards it actually being a deleted subdial 5100 rather than the lower beat 5012, I hope to get into the movement to physically check when I get a chance.
There were some other variants as well, the Bell and Ross branded M1, the Kobold 323 Pilot Chronograph branded one, in addition to a few obscure bespoke ones such as the 'Fulda Challenge' and the 'Project take Off' editions.
So, the first generation, here are a few examples:
An early catalogue picture:
Another two examples:
( Jean-Michel )
And one currently for sale on Chrono24:
On all these examples the main hands are infilled, rather than complete lume as far as I can see, the chrono hands appear to be orange, swept wing types except for the one on Chrono 24. This leads me to assume that the main hands on mine are service replacements and perhaps so too are the chrono hands, the straight wing style seemed to make an appearence in the early to mid nineties, so again I presume this is when mine were changed if this is the case. To be honest, I prefer the main hands fully lumed but would have preferred the original chrono hands, but it's not at all a big deal.
So, this is mine:
'Sinn' crown and raised crystal:
Sinn style early 'roller' bracelet:
One of the things to notice is that this one also has an English day wheel (although I have the original German day wheel seperately).
A very bare case-back (except the small 5 figure serial number):
In the wild:
On the wrist:
For interest, here is a pic of the extremely comfortable extendible bracelet -
And finally, a brace of Sinns -
As ever, any comments/corrections/observations are more than welcome, hope that's been of interest