Time keeping / Date variation
 

Hi everyone,

I bought a brand new sub c by an AD about 10 days ago and I noticed something pretty strange.

Of course as soon as I got it i set it to the correct time by synchronizing it to an atomic clock. After 24 hours i checked to see how many seconds it had gained/lost and it turned out that it was 3 seconds fast. I thought it was cool because it's well within COSC standards.
I checked again the next day, and the day after and it stopped gaining time: after 3 days it was still at +3 seconds....so it gained 3 seconds the first day, 0 the second day and 0 the third day.
I checked again on the 4th day (yeah, call me paranoid, hahah) and all of a sudden it had gained 4 more seconds, so I was at +7 total in 4 days.
Didn't check for a while and today I checked again and it's +8 seconds.
I'm really happy that the watch has gained only 8 seconds in 10 days (i think the accuracy is terrific) but I'm somewhat worried about the variance. Shouldn't it be gaining/losing the same amount every day?

Now, regarding the date, I noticed that it doesn't change at the same hour every night. Since I had the watch it happened to me to see the date change 4 times...twice at 00:04 (different seconds but same minute), once at 00:02 and yesterday night at 00:05 and a bunch of seconds.
Again, is this normal? I know the date change almost never happens at midnight, but shouldn't it be happening at the same time every day?

I think my watch is fully wound, I gave it the 30 turns the first time and gave it 30 more after 5 days...I wear it about 16-18 hours a day so I don't think it should lose charge. I only take it off to sleep (6-8 hours depending on the day) and I leave it face down next to my bed.

thanks in advance to everyone who will be able to enlighten me! (and sorry if i'm sounding paranoid, i'm just curious)

The short time you have worn it is not long enough for the watch to settle into a pattern. Wear it in a regular pattern for a few months and see where it stabilizes.
Based on the hours you wear it it is not necessary to wind it as IMO random winding breaks the wear pattern.
Just my 2c.
Post your findings.

As for your date change variance - yes you are paranoid.:chuckle:

Have to agree about the paranoid with the time and date my advice just wear and enjoy your watch its fine.

The variance in the date changing is absolutely normal.

My experience is that watches do not lose or gain the exact same amount of time every day, much of it depends on what you're doing on any given day.

If your watch were losing five one day and gaining five the next and losing two then gaining seven etc., you might have something to worry about, but from what you've described, your watch appears to be working perfectly.

My Sub C behaved similarly to yours, at first I too incorrectly assumed that a watch would gain or lose the same amount of time every day, however when all is said and done, if your watch is accurate to a few seconds a week, you have an extremely accurate watch and you really shouldn't be worrying about it. :)

Over time, you can get a sense of how much it gains/loses, and experiment with nightly resting positions, which will at least somewhat offset whatever daily loss or gain you're seeing.

Thanks for the answers everyone!