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Discussion Starter #1
Figured I'd ask around a bit before I did too much experimenting...





Right now, I'm running about .030" striker engagement. The top of the sear has been shaved to achieve that. I have also cut the rear of the sear a bit at what I am thinking is too much of a positive angle.



I can pull the trigger and watch the sear move across the striker. If I release the trigger before the striker releases, the sear will return to it's fully upright position. While I can watch and feel the movement, it's nice and smooth, but I would like a crisper break (i.e. less Glock-like
).



The trigger is currently ~4.75lbs, and I'd like to get that down to ~3.5-4. I'm thinking of cutting the top down a bit more to get to ~.025-.028" engagement, and then cut a bit more off the back of the sear to get to a more neutral angle... Does that sound about right?



Thanks,

Dave
 

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put some marker on the striker and then dry fire it a few times make sure the sear is making good contact with the striker the more contact between the two the less you can actually feel the interaction. also make sure you put a good shine on them both.
 

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Discussion Starter #3
Thanks Dan!



I suppose I could mark up the whole face of the sear too, and then I'd be able to tell if it is just the tip of the sear making contact or the whole face...
 

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When I do them only the top of the sear contacts the striker so I don't bother with marking the sear.
 

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Discussion Starter #5
Hmm, still no good...



I marker'ed up my sear and striker - just the very edge of the striker is contacting the sear, so the striker is riding across the 'hump' of the sear instead of the sear riding across the striker.



So, I took the sear down to .029" and redressed the angle of the hump hoping to get the sear to ride across the striker... But no change.



The first time I cut the sear I cut the top down to get to ~.035" engagement, and cut the back of the sear at as steep of an angle as I could without touching the rounded part with the stone such that the cut that I made was ~.035" wide (the striker just barely covered the cut when looking at it from the rear with the gun assembled).



I have not cut an angle on the striker at all - just polished it up a bit (can still see a few factory machine marks).



After all my work I'm still just under 5lbs. ~2lbs worth of trigger return spring, ~1/2 lb of sear spring, ~1/4 lb of FPB, and the rest is sear-striker interaction...



Maybe I should buy another sear and just cut the top to get to ~.030" engagement and leave the rear of the sear alone? (idea here would be to have more of an angle on the rear of the sear in the hopes that only the tip will touch the striker)



Thanks for the help Dan (and anyone else that might have an idea) :?
 

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Krautwagen,



Did you cut the front part of the sear that contacts the trigger bar yet when everything is put together in the gun? It's the half circle shaped part on the sear that needs filed down to almost a pie shape with a radius on it.



Better yet, with Dan's permission, he might post the link to the instructions he made. Have you seen his instructions yet? You need to read this carefully.



It sounds like you are making progress though.
 

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Discussion Starter #8
Yes, I did. I cut that an an angle that matched the trigger bow and then rounded it slightly... Not sure if that's the wrong way to do it or not...





Update -

I put a bit more of an angle on the sear, so now it rides on the striker correctly. I rechecked my engagement and it was ~.040", so I knocked the sear down to ~.030". Doing this eliminated at least half of the squish/creep in my trigger.



It was still ~5 lbs, so I decided to play around a bit... Ran to the hardware store and picked up a few springs... Modified a 3/16" diameter (.023" wire) tension spring to the correct length for a new trigger return spring. All I can say now is that I REALLY hope this works out during live fire, as the trigger is now damn near perfect. Trigger guage shows 4lbs 5oz - the break is crisp and the reset is just fine (contrary to logic and popular belief)... Hopefully I'll get some range time this weekend to test it out. I think I'll still carry the original and some tools just in case it fails on me.



Thanks again for all the suggestions & help,

Dave
 

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Discussion Starter #9
Jeff, yup I did. I actually downloaded those long before I bought the M&P. Also, those instructions were sent to Dan by someone else - he hosts them for us though
I'm sure he and David have a few extra tricks up their sleeves, as I can't see how it'd be possible to get lighter than ~4.5 with those instructions (without changing to risky contact angles or changing springs).
 

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Krautwagen,



Good job. I didn't want to post Dan's link blindly around out of respect for his investment in making the power point slides.



I know from another posting we were chatting about this and you were h**ll bent on the spring change. You know more than I do.



Awsome job though on getting your pistol up and running again. I know its a good feeling.
 

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Discussion Starter #11
Got out for a 100 round test session today - not one problem whatsoever... I'll update again after a few hundred more to see how things hold up
 
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