Smith and Wesson Model 629 timing and Smith and Wesson Model 686 and Model 66 timing

[Roberto Renauld]

Dear Smith and Wesson Forum Owners
Some years ago I had a Smith and Wesson Model 27-7 with 6 inches barrel it was a brand new gun, just mint out of he box!!!!, to my surprise I had timing troubles with it after 250 rounds fired with regular Winchester 158ge JSP factory ammo!!!!...
Here in my Country Argentina, it is very difficult to solve this timing problem, we have no good gunsmiths to accomplish this work.
I have read a lot regarding this timing problems in S&W new products, nevertheless I am an enthusiast of this brand off revolvers, I have owned several of them: Model 19-2 4 inches, Model 10-7 2 inches, Model 17 6 inches, the above mentioned Model 27-7 and at the present time a very very nice, and good shooting piece Model 10-9 pencil barrel 4 inches with no timing problems at all!!! 3 inches groups at 25 meters!!!! with standard 158gr Round Nose lead bullet, a real joy to shoot with!!!!..I must try a new box of Remington 148gr WC match Target load yet!!!!....
I am very interested in 3 new guns :
I like the Model 629 with 4 inches barrel
The model 686 with 2 1/2 inches barrel
and the Model 66 with 2 1/2 inches barrel
I read that the Model 629 4 inches or 6 inches needs retiming after firing 1300 regular 240gr JSP ammo.
Is this so???????.....only 25 boxes of factory ammo???? then call the gunsmith please!!!!!.....
However I have no experience read on detiming trouble with Model 686 or Model 66 in 21/2 inches with regular 158gr 357 ammo.
I shall be very pleased if you shoul favour me with your own experienced advice and suggestions!!!!
Best Regards
Roberto Renauld
[email protected]

 

[deuterij]

Roberto,

I have experienced timing issues on nearly new model 29s - specifically a 29-2 and a 29-5. The issue I note is that when applying slight finger drag on the cylinder while cocking single action, the cylinder stop does not quite drop into its slot before the hammer locks back into full cocked position. This also happens if the gun is cocked very slowly. If I were to drop the hammer in this condition, the chamber would be misaligned to the barrel by a tiny amount. Also, the recoil motion could cause the unlocked cylinder to rotate back resulting in the fired round being under the hammer after next cocking cycle. I have posted on this in several other threads and it seems others have experienced this problem, even if they were not quite aware of it. One would likely not notice it unless one performed this very specific test because most people cock the hammer rather quickly and don't have cylinder drag. People have told me that applying cylinder drag or cocking very slowly are not realistic ways to test carry-up; however I have had several guns get cylinder drag at the range after a few rounds have been fired. I believe it is a realistic test and that the revolver mechanism should positively hand-off carry-up rotation from the ratchet to the cylinder stop.

My 29-5 is at S&W for a second attempt at remedying this problem. After the first attempt, they sent the revolver back to me and it failed my test again. So apparently they are not aware of the problem. I am sure their standard test is to cock the revolver quickly with a free-spinning cylinder. Then inertia completes the carry-up and everything seems fine.

The 629 is built to the same dimensions so I would expect it to have the same problem. I suspect models 27/28 are also built on a similar N-frame design, but I have not found the problem on either of those.

I own models 66, 586, and 686. I have not found any carry-up problem in these models, nor have I read about any.

I hope this helps, and I wonder what others will say. I realize timing is a mechanically sensitive issue. Tolerances must be tight in order to guarantee positive mechanical hand-off from ratchet to cylinder stop. If done wrong, it could lock-up the mechanism as ratchet fights against cylinder stop. All revolvers I have except the m29s pass my test just fine, so I know it is possible.

 

[Roberto Renauld]

Dear deuterij
Thank you very much for your experience sharing regarding TIMING in S&W Model 29 revolvers.
Yours Sincerely
Roberto Renauld