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Discussion Starter #1
I have an MP40. Out of the box, the trigger was VERY "crunchy" or "gritty" from start to break. After cleaning and lubing, the grittiness was reduced (to a shorter section of the overall travel), but not completely. Running 100 rounds through it after that did not seem to make any improvements. I feel I was very careful about where I applied lube to the trigger mechanism.



Example of trigger pull (hope this makes sense):



>--smooth--gritty|stop--pull harder--break)



Each of these "phases" of the trigger is pretty small but that "crunchy/gritty" stutter right before the point where I have to apply more pressure to actually fire the trigger is quite noticeable. The travel up front, before the gritty section is smooth and light.





My question(s): Is this just the way a stock MP trigger is? Should I send it back to S&W, or is this normal OOTB and maybe it just needs a trip to Dan for a trigger job? Or is this normal and a few more hundred rounds through it will smooth it out automatically? If it wasn't for the gritty section, I would be happy with the overall trigger feel.
 

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Take the striker mech out and clean lube that area. I believe what you are feeling is the striker safety. Clean really well, and only lube the areas that the book says.
 

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Discussion Starter #3
When I field strip the gun and move the striker by hand, it is smooth. Also, when the slide is off the frame, the trigger is smooth front to back as well, even with the mag safety lever held up while pulling the trigger.



Are there instructions somewhere online detailing how to "remove the stiker mech"? I'm certainly not even close to being an expert on handgun internals. I mean, I can field strip fine, but anything much more than that gives me the hibbi-jibbies given my lack of mechanical skills. :?
 

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I used Dan's instructions for trigger smoothing, but I noticed the safety stop piston hole was very rough and need smoothing with 800 wet paper. Following the polishing the piston stop and slide hole, made a major improvement and got rid of the gritting feel
 

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Discussion Starter #6
I think you guys are right about where the grittiness is coming into play. I tried just lubing the bottom of the safety where the trigger rubs against it after spraying some BreakFree around it and working it in and out a few times by hand -- and it made small difference for a few pulls. Not dramatic, but enough to make me think you're correct in your diagnosis.




The piston moves in and out smoothly by hand, so I don't think it is the piston hole, though. But it does appear to be the interface between that safety and the trigger.



My problem is that along with a severe lack of delicate mechanical skills, I also lack the tools necessary to perform the operations described in the instructions (set screw screwdriver and sight punch for example). Somehow I think I trip to Dan is in my MP's future.
 

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Dan is excellent and can take care of any of your problems. You'll be amazed how smooth it will be after one of his trigger jobs.
 
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