S&W 59 doesn't fire in single action

[jrp16]

I have a S&W model 59 9mm semi-automatic SA&DA pistol.
After its last cleaning disassembly/reassembly, it stopped firing on single action. that is, it takes 2 trigger pulls to fire. after firing the hammer stays back cocked as normal, and pulling the trigger releases the hammer but no firing; pull the trigger again and it goes through the double action and fires as expected. next pull releases the hammer, but no fire again and repeats. This action is consistant with other magazines and other ammo. I assume I got something out of place in the reassembly, but I can't see what. any suggestions?

Jim

 

[James K]

I think it goes without saying that you got something in wrong, but I have been sitting here playing with one of the darned things and I sure can't figure out what you did to cause that problem.

I will say that those are not the easiest pistols to dis- and re-assemble beyond field stripping, and are best left alone unless parts need to be replaced.

Can you tell if that first hammer fall is all the way, or if the hammer might be stopping on the half cock notch. With pistol unloaded (I have to say that or folks climb all over me) do the exercise you described and compare the position of the hammer the first time against where it is the second pull when the gun would fire. It could be that the sear is dropping into the half cock notch, but I really can't see how that could happen with the Model 59.

All I can suggest is taking it apart again, checking each part to be sure it is in right and functions, and reassembling.

Jim