A couple months ago I posted about buying a new 3" 686+ and having it misfire because of light primer strikes.
The local gunsmith took a look at it and ended up replacing and tightening the strain screw. This had the desired effect of getting 100% reliable strikes with good primer detonation. Unfortunately, the trigger pull went from 10# to 12# or more, but I figured I'd give it a little time to wear in before messing with springs and such.
A few forum members suggested I try an over-sized firing pin, which I ordered but have not installed yet, since it has been firing reliably.
So now I've fired the 686 a few times, mostly focusing on reliability, but found the accuracy to be wanting. I consider myself to be a fairly average shot and I thought that I just needed to get the sights dialed in and learn to shoot this particular DA revolver a little better.
But the accuracy thing started to bother me, so today I went to the range with factory ammo (HPR 125 JHP) and a sandbag. I ended up cranking the rear sight all the way to the right. At the end of the day, I got two 4-round groups at a little over 10 yards that looked like this:
As you can see, the groups have some vertical stringing that I'm probably responsible for, but overall there is still a left shift. (And this was with the sights cranked all the way to the right.)
So I took the 686 back to the dealer and talked to the in-house gunsmith. He seems to feel that there is a couple degrees of barrel cant and will try to reseat the barrel. He warned me that he may need to shave to barrel shoulders to get it to seat right, and that we could end up doing a lot of work to ensure that the forcing cone and cylinder gap specs are maintained.
He also said he'd do an action job and see if he could improve the trigger pull. (He didn't feel an oversized firing pin would be useful in doing this.)
I'm developing a love/hate relationship with this gun.