Single action not working

[HI5-O]

A technical question.

I just examined a S&W 629. The double action trigger pull works normally, pull on the trigger, the hammer goes back and then fires.

Problem is when I cock the hammer into single action. The hammer stays back but when I start to apply pressure to the trigger, something pulls the trigger forward and the hammer lowers but is stopped short of having the firing pin hit the primer.

Now if I have the hammer cocked and just jump hard on the trigger, the hammer falls and will probably fire.

All of the above testing was done without live ammunition and the firing pin is mounted on the hammer.

Can anyone tell me what may be wrong with this gun?

Thanks

[Toolguy]

That is called "stubbing". What happens is when the hammer falls, the sear catches on the top of the trigger and pushes the trigger forward with it. It is usually caused by too much material being taken off the back part of the trigger during an action job or by a trigger stop being set too close.

A new trigger is usually called for, but each case must be considered on it's own merit.

Edited November 19, 2013 by Toolguy

[HI5-O]

Thanks for the info, appreciate it.