Typical SPD deviation range for Omega 30 mm calibers?

Specifically, caliber 268. Just curious what the range of SPD deviation might be for a well regulated example.

Hmmm...sort of a difficult question to answer what is "typical"...you will get people that will claim very good accuracy from these no doubt, but you don't often hear from people when the accuracy is mediocre or poor.

Here's what Omega required up until recently:

All checks done over 3 positions, and those are dial up, crown down, and crown left.

At full wind the average rate (average of those three measured positions) should fall between -1 and +16 seconds per day. The Delta, which is the difference between the fastest and slowest position, can be as much as 40 seconds.

At 24 hours after full wind, that Delta can increase to as much as 50 seconds.

Keep in mind, this is only over those three positions, so other positions can be tighter or looser - they simply aren't measured.

So if you do some even simple math here, you can see that the range of rates that this movement can run in a given position, and still be within Omega's specs, is very large. If you happen to wear the watch in a position that runs at the extremes of what is allowed, then the watch is not likely going to time well on the wrist.

Now the latest updates to these tolerances are a bit different, so the average daily rate at full wind is now from 0 to +18 seconds per day, and the Delta at full wind is 30 seconds, and 24 hours after full wind is 40 seconds. So they have loosened the average rate, but tightened the Deltas - odd but whatever.

Note that these tolerances apply to all of the 30 mm movements, even the Rg variants that were chronometers - Omega doesn't expect them to run any better than the non-chronometer versions.

The reality here is that how the watch runs will depend on what condition it is in, and how much care was taken as the last service. Keep in mind that sometimes compromises are made because not many parts for these are still available from Omega, so less than perfect parts may be put back into the watch, unless you are going to pay up for expensive new parts, or expensive restoration of old parts (repivoting and things like that).

From my own experiences, I've had some that run very well after service, and some less so. Omega's tolerances are sort of the minimum standard that is acceptable IMO...

Hope this helps.

Cheers, Al

Very helpful, Al. I’m getting roughly -22 SPD on my Geneve 2903 24 hours after a full wind, so that seems within range if I’m understanding your post. Not on par with the caliber 551 movements in my vintage Constellations, which are astonishingly accurate, but still pretty good for a 62 year old watch. Thank you very much for the information.