Accuracy of 7-day automatic movements?

Anecdotal evidence seems to suggest that 7-day automatic movements tend to be less accurate than regular automatics. I have no intention of creating an issue where none exists, so I would be grateful if owners of 7-day automatics would be kind enough to answer any or all of the following questions:

• what is your watch's observed accuracy?
• why do you find these watches (more) attractive: a) convenience; b) technical achievement; c) power reserve indicator; d) some or all of the above; e) other reason(s).

This is not a gratuitous question either: while I can't see myself wearing any Big Pilot on account of their size, I'm pondering whether my next purchase should be a Portuguese 5001/5007 with white face and blued hands.

Many thanks

Well, I think the ref. 5000 was the first IWC with a 7 day power reserve, released in 2001.

Many other models with 7 and later 8 day power reserve followed till today.

Time by time some rumors point to accuracy problem with those movements, but NOT in general.

About 15 years of experience with these technology should be a base for trust.

Mine is the 5001/09 on a brown Santoni strap. it normally gains about 30 seconds over a 36 hour period, but still one of my favorite watches.

The brand name IWC is reason enough for me to trust almost anything they deem good enough for release. I wasn't implying that there are any problems either with those movements - but if they are inherently less accurate, that's good to know before purchase.

My experience with 2 different Portuguese-family 7-day PR watches suggests that they hold their excellent timing over the course of the 7 days with little, if any, variation. However, I do not find it convenient to let the watches run down beyond a couple days because the rewinding is hard on my finger-tip and thumb. I'm not kidding!

If you are worried about the accuracy of the 7-day movement, I would suggest you to check out the latest Portuguese 7-day. It has a brand new movement with double-barrel, making it more accurate than its predecessors.

When I first acquired my Portuguese 5022, in which the 7-day movement is powering the entire watch including the perpetual calendar module, I kept track of its rate and was astonished to find that it was ONE SECOND fast after ONE MONTH!!! Your results may vary...

Results vary.

I purchased my 5001-07 and 5009-01 in a span of 1 year from each other and they seem to be the latest batch of calibre 50xxx with ceramic parts for the winding pawl.

1. 5001-07 average of +7.5 seconds per day
2. 5009-01 average of +2.5 seconds per day

I can confirm this with my 5022.

Congratulations, David. You are now a Master! I didn't notice that in the other, rather heated, discussion. ;-)

I have IW500109- average gain per day is 5 sec

My ref 5001 is from 2008 and was serviced 4 months ago and fitted with new winding ratchet and ceramic pawls. It varies between +1 and +2 seconds a day, from full 8 days down to aprox 3 days of power reserve. It is my most accurate watch in terms of same difference each day, wether lying down or walking all day.
I like to think the new caliber should be even better. You will love it i am
sure !

• My BP Le Petit Prince runs between between +1 and +2 sec / day
• I find it attractive because it is
  d) a very convenient technical achievement to have a power reserve indicator that shows you 7 days of power reserve.
  e) The automatic winding is very effective. It needs very little wrist movement to build up a significant power reserve. Though it never got below 5 days of power reserve left because
  f) it's such a beautiful watch!

I have 3 BP. All run about 3-5 sec fast/day. One of them was at 12 sec fast /day but after 5 years I sent it in for a routine service and they regulated it to about 2-3 sec /day. It is still at that rate and no problems. I think they all leave factory running a bit fast but clearly the movement can be regulated to a high level of accuracy.
I love mine, love the beauty of it. I never found it too big.

I purchased a 2009 500109 at the beginning of November. While accuracy was never my main driver (I just love the look of the watch), I was astonished to find that it lost just 5 seconds in the first 30 days. I find this level of accuracy almost intimidating...

Lorenzo

Hi,

My IW 500107 is currently running -1 sec a day which gives only about 30 seconds per month discrepancy. I'm really impressed. Oh, and it is simply the most beautiful watch from IWC collection IMHO. The power reserve indicator is not that useful to me due to the fact that I wear the watch on daily basis and honestly do not remember when I had to wind it manually. However, it nicely balances the dial and is very useful to those who wears the watch occasionally.

Cheers
Juri

Hi Guys,
As some of you know, I am the proud owner of the IW 500114 .
I was aware that the 51011 calibre tended to run fast as most owners would attest. But it certainly did not put me off buying the watch.
Ive had mine for 10 months now and it runs between 8 to 10 seconds a day fast. That being said, when she goes in for the first service Im confident that IWC will be able to regulate the movement to a more satisfactory 1 to 3 seconds a day I would guess.
Cheers
Neil.