[rgbeaty]

I recently replaced grips on my P938 (that may or may not be significant). About 2 weeks later while routinely shooting, the trigger became hard to pull and when the mag was released, the disconnector bar fell out. Now the hammer will not cock automatically with shooting. The gun shoots fine otherwise. The hammer will cock with manual racking. Any suggestions for how I can repair this or does it need to go back to Sig?

 

[drband]

I would suggest a trip back to Sig. it may be as simple as sear & hammer pins not being in place or it could be more significant. Personally I would not shoot it in this condition. If the disconnector fell out, the trigger bar likely was out of place, too, somehow.
Is your main trigger pin still in place in the frame?

And yes, changing the grips could have led to something getting out of place.

 

[rgbeaty]

The trigger appears to be in proper position and it does shoot otherwise normally. I'll heed your advise and not use it until repaired. Thanks.

 

[ThnkFrst]

I would say that the grip replacement is significant. On the P238/938, the trigger bar is "sandwiched" between the left grip panel and the mag and that helps keep the bar positioned under the disconnector which keeps it from sliding out of the notch in the frame. An aftermarket grip panel may not be providing the proper support or may even be pushing the trigger bar out of position. What brand grips did you install?

If the disconnector is missing (or not positioned over the trigger bar), the trigger bar won't be pushed down to clear the sear as the slide cycles during firing and the hammer won't remain cocked. If you manually cycle the slide, the hammer will remain cocked but only if you release the trigger before racking the slide.

Have you reinstalled the disconnector?

Edit: Here's a pic of the disconnector. Note, the top of the disconnector angles UP to the rear of the pistol.