Model 69 problem

[brick]

I purchased a used model 69 a while back and upon receiving it I dry fired it and it felt "crunchy". I took it to my gunsmith to find out why it was "crunchy". After his inspection and trials, he returned it to me. It is not "crunchy" anymore but according to him, if you dry fire it, it is okay. If you introduce recoil into the mix, the firearm will irregularly lock up. In addition to the original hammer/trigger/sear, he has installed two additional hammer/trigger/sear sets (one from his personal model 69 that has a PC hammer/trigger/sear set) and the firearm locks up with recoil. He also installed a longer firing pin to make sure that the primers were hit each time. He is stumped as to why the firearm will lock up at odd times when fired. According to him, this is the first Smith revolver that has beaten him. Anybody have an idea why the irregular lock up with recoil? Thank you for your help.

 

[snw19_357]

What locks up? Trigger resets but then can't pull again? Hammer? Cylinder opens and turns freely?

 

[toad67]

The internal lock?

 

[brick]

The cylinder opens and turns easily. I am told the hammer and trigger lock up and have to manually move them to allow the firearm to shoot. I have not shot the firearm yet.

 

[Toolguy]

Knowing when in the cycle it locks up, and what part(s) quit moving will provide some clues.