My model 69 will occasionally not "carry up" and lock into position when the hammer is thumbed back in single action mode. It doesn't do it all the time, just every so often. In fact, I have a hard time duplicating this issue, and it only happens when I am shooting it, never on dry firing. What is the cause, and how is this best corrected?

I would start a good deep cleaning and lite oiling.

Send it back.

After completely breaking it down and cleaning it, I'd try to figure out if it's random, or always happens on the same cylinder. Go from there.

Wonder if you are slightly working the trigger under recoil. As gun recoils some people slightly release and re squeeze the trigger, this moves the lock and the hand a bit unlocking the cylinder and then the hand doesn't engage the next tooth on ratchet. Another possibility is a bolt spring that ia bit weak releasing the cylinder under recoil, or a tight cylinder notch not letting bolt fully engage on that chamber, or hand is a bit sticky its window and not always moving forward to engage ratchet. Not fully releasing the trigger after firing (short stroking) can also cause this, as trigger needs to move fully forward to fully stroke the hand, also can be caused by sticky rebound slide or weak spring not fully resetting the trigger.

I once got a great deal on a 19-3 because it would not always rotate the cylinder cocking. Out the door, a can of carb cleaner and it never failed again. Just some gunk

I'll do some more investigating and see if I'm "working the trigger" as Steelslaver mentioned. I hesitate to send this gun back because I polished the underside of the rebound slide, and hammer stud and changed out the factory spring with a Wolff 11 pound spring. I could easily re-install the factory spring, but there's no way I can replace that black coating on the underside of the rebound slide! I prolly voided the warranty? Anybody have any
"warranty issues" like that?

I have returned a couple revolvers that I'd polished.
Only issue at the Factory was having an Apex firing pin replaced with stock.
The did return the one they removed.

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-jwk-
US Army '72-'95

Hello, I never had that problem with mine, I hope it's not serious, I sent my new one back a week ago!
Good luck
SEMPER PARATUS

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NRA Life Member
CPO