I've gotten the 3rd gen auto bug. Recently bought 2 used 915. On one, doing a dry fire function check, everything works fine. But with live fire, after the 1st DA shot, the trigger won't reset on it's own. You can push it forward w your finger to reset, fire again, same thing. I put in new recoil spring, hammer spring, & trigger return spring. Still happening. 115 gr & 124 gr, fmj & hp ammo. Factory loaded ammo. Does the disconector or trigger draw bar need replacing??? Any ideas?? Thanks

Have you done a complete dissassembly and cleaning? Does it happen with all the magazines?

The drawbar might be binding, either on crud, or in it's frame slot, or on the magazine. Look for shiny spots on the sides of the magazine as indicators of contact/binding.

Also, check the trigger play spring for damage. In addition, check the trigger plunger and spring located inside the top of the trigger. It should freely plunge down and back up. (it's under very heavy spring tension)

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Ret. LE, FA Instr, S&W Armorer

There was a shiny spot on top of the old mag that came with it, just thought it was old age. I did a complete frame strip & cleaning. If it were the draw bar binding, or a spring issue, would it not show up during dry fire function check?? It only happens during live fire...

Perhaps. You could also check the bottom tail of the disconnector, and the disconnector angle cut in the drawbar for burrs.

With the slide off, if you push down on the top of the disconnector, does it return upward when released?

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Ret. LE, FA Instr, S&W Armorer

Found some old tool marks on the draw bar. The old mag was worn smooth, new mecgar 17rnd just wouldn't pass lol. Gonna smooth those out & go from there. Thanks

I cleaned up the tool marks on the draw bar, polished everything up nice & smooth. Runs great now. Thanks for the help!!!