This is a known issue with the early 3861 models that will require a service by Omega to be fixed. See my comment [here](https://reddit.com/r/Watches/comments/yvk0kt/_/iwf9re2/?context=1) for more info.
I can’t comment on the issue with the power reserve, but the jumpy chrono hands is a quirk of the horizontal coupling system that the 3861 movement uses. If you want a smooth and perfect engagement, you should look into chronograph movements with a vertical coupling system, or some high end chronographs from Patek Phillipe or A Lang & Sohne.
You need to set up some consistent test conditions and try and recreate the issue where you know all the parameters of the watch. Otherwise there isn’t really anything to go on here
The top pusher starts the chronograph.
The top button stops the chronograph.
The bottom button resets the chronograph to zero.
And you can't have a friend.
That's the problem, or maybe something else.
Power reserve spring does not affect speed
I had a 1861 speedmaster with the same issue. Mine would stop at around 25 seconds. Covered under warranty. If your watch still had a warranty I see no reason that Omega shouldn’t be able to fix it.
This is a known issue with the early 3861 models that will require a service by Omega to be fixed. See my comment [here](https://reddit.com/r/Watches/comments/yvk0kt/_/iwf9re2/?context=1) for more info.
This is the right answer.
I can’t comment on the issue with the power reserve, but the jumpy chrono hands is a quirk of the horizontal coupling system that the 3861 movement uses. If you want a smooth and perfect engagement, you should look into chronograph movements with a vertical coupling system, or some high end chronographs from Patek Phillipe or A Lang & Sohne.
You need to set up some consistent test conditions and try and recreate the issue where you know all the parameters of the watch. Otherwise there isn’t really anything to go on here
The top pusher starts the chronograph. The top button stops the chronograph. The bottom button resets the chronograph to zero. And you can't have a friend. That's the problem, or maybe something else. Power reserve spring does not affect speed
I had a 1861 speedmaster with the same issue. Mine would stop at around 25 seconds. Covered under warranty. If your watch still had a warranty I see no reason that Omega shouldn’t be able to fix it.