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Discussion Starter #1
I have looked at Dan Burwell's (thanks, Mr. Burwell) walkthrough on the trigger job. I think I understand most of it, but I am not sure what is meant by the section that describes how and where the striker engagement face of the sear is modified. I understand polishing, but I am not sure what is intended when it says "cutting down the hump," "don't make a negative angle," and "this is not a simple angle cut." Can any one help a little more? Thanks.
 

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They are not my instructions I just host them for all to see.



I don't like cutting down the "hump" I think it can make the trigger a little mushy. It is when cutting the hump that you have to be careful not to make it less then 90 degrees to the top of the sear.



Now I am in favor of cutting down the top of the sear. This is where they are talking about it not being a simple angle cut. you have to cut the whole top of the sear down not just an angle cut on the back side. Just don't get your sear to striker engagement less the 0.030 in.
 

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Discussion Starter #3
I thought those were your techniques.



I understand about the negative angle. That makes perfect sense.



By the hump do you mean not to cut the flared backward portion of the sear as you look at it from the side?



By cutting the top, do you mean that you cut down the top surface of the sear as it sits in the gun, leaving at least .030" engaging the striker? Leave the flare/hump alone and "lower" the top to touch less striker? Do you have to cut the whole top of the sear so it remains flat?



Do you agree with that trigger job's method of modifying the engagement of the trigger bar and the sear?



I am sorry if I am being dense, but some of the written descriptions aren't translating into the picture in my head. Is there a photo or a diagram that shows where you like to modify the sear? I made this drawing that shows what I think you mean.



Also, if you don't want to reveal your methods, I understand. I have generally hired a gunsmith to do this sort of work, but on this pistol I have the idea I want to try it myself. If you were just down the road, I'd probably bring my gun to you and consider it money well spent, but the shipping will more than double the cost of the trigger job. Plus, I really do want to learn to do it.









Thanks, again. I appreciate your patience.
 

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What you are calling the flare is what they are calling the hump.



I remove keep removing metal from the front of the sear where it contacts the trigger bar until the gun will not fire any longer then I remove from the top of the sear until it will fire again. this will usually leave you with about 0.040-0.030 engagement with the sear. Unless you figure out what you are doing I would recomend leaving it at this point any further and you risk ruining parts.



The only way I have found to reliably check sear engagement is to color your striker with a sharpie put the gun together and dry fire it a few time the remove the striker and measure how much of the sharpie has been removed.



By now this should be as clear as mud right :wink:
 

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Discussion Starter #5
It makes sense now. Using the same terms helps, and making the drawing I made and then looking at the relationship of the parts in the gun helped too. Thanks for your tips and giving your method.
 

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Flare -vs- Hump

with NO disrespect to the author of the wonderfully appreciated instructions, I vote for the nomenclature "Flare" over "Hump".



Now, jhe888, could you show on your nifty drawing, colored in red, the material to be removed?

The rectangular-ish area that contacts the trigger bar has a circle in its center, due to its manufacturing molding, I gather. If you could add this circle to your drawing, it would be a good reference to show how much meat gets removed down there. Not to put pressure on ya', but your drawing looks pretty good, so me thinks it's fairly easy for you to do. (?)



Cheers.
 

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Discussion Starter #7
Except I don't know how much to show to remove. I plan to follow Burwell's instructions about how much to remove. I don't think you can show it and do it by eye. You do it by function.



Edited to add a modified drawing to show where the cuts are. Do not use this to determine how much to remove, or what exact shape the part that the trigger bar bears on should be. The drawing is not exact, and not to scale.



I am not an expert, and have made this drawing to help myself visualize what to do to the sear. If anyone has any comments or suggestions, or if I got something horribly wrong, I hope you will speak up.



 

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Dan,

What is the typical OEM sear engagement?
 

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Nice drawing - what a guy!

That's great - thank you.

I've already done mine, but such a drawing might have helped me feel more confident before starting. As for me, I cut down the hump as far as I could without going "negative" ... this was per the instructions hosted by Dan on his site (not HIS writing, for those who still don't get that). I did this before I read Dan's explanation of how he does it. She shoots good, but we'll have to see if she wears down and causes trouble later on. I'd like to get a couple of sears to experiment with - specifically, using Dan's technique of removing the front until she no shoots, then lowering the engagement. After taking out the Sear Housing Block umpteen times, I can do it pretty readily, so fitting and checking throughout the process is simple to do.





I hope Jester lets us know when he gets his order in ... as S&W doesn't seem to want to sell directly to consumers (?).



Shoot Well!
 

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Discussion Starter #13
Smith does not have individual sears for sale (or safety plungers). The guy said they plan to, but not yet. The sear block assembly is available, but that is a part restricted to armorers. I don't know whether that will apply to sears alone.
 

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I emailed an inquiry ...

... about the availability of replacement Sears yesterday, but have not yet received a reply.



Their parts list does have an asterisk next to the Sear Housing Block Assy, which, indeed, has a footnote: "restricted to factory trained armourers".



Brownells offers 2 of the 3 varieties the Sear Housing Block Assys. ... but not the one that I would need anyway (No IL, No MS). I called Brownells and they said that THAT particular part was dropped from their list????



Perhaps a call, instead of an email, is the way to go when dealing with S&W.

The guy who answers the phone might be a bit more liberal than the reps. answering emails.



I'll post a copy of the email I get back ... if'n I git one!
 

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When I buy sear blocks I buy them with the IL and Mag safe, then I can configure them any way I need to. The IL and mag safe are very easy to remove.
 

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OK then ... I gather that all three flavors of the Sear Housing Block ("standard", "No IL", and "No IL, no MS") share the same exact base components. Any one style can be converted to any other by adding or removing the IL or MS components. I had hoped this was the case, but wondered if there were other differences that might not allow for such interchangability.



One of the reasons why I was not sure is the odd pricing on S&W's site.



std. .................. 28.92

no IL .................24.75

no IL, no MS ......25.77



I find it odd that the "no IL, no MS" is priced higher than the "no IL". If it's just missing one component, I'd expect it to be cheaper, not a bit more. There I go again, trying to be logical about retail pricing = it's all random!



Thanks, Dan!
 

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jhe888 said:
Smith does not have individual sears for sale (or safety plungers). The guy said they plan to, but not yet. The sear block assembly is available, but that is a part restricted to armorers. I don't know whether that will apply to sears alone.


I just recieved another shipment of parts directly from S&W.

Yes, they have plungers for sale; I have them in my hand right now.



None of the parts are restricted to armorers. That was the original plan by S&W. You can thank a few members here, and myself, for getting this changed.

 

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Discussion Starter #19
I called too. Should I ask for someone in particular? Do I need to know the secret countersign?



Seriously - I did call and got the response I described. Now, it did sound like the guy was reading from a catalog or a computer, so he may not have been the right guy. If you can tell me how to penetrate the bureaucracy and get a sear and a plunger I'll be grateful.



Or would you sell me a sear and a plunger Yukon?
 

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800-331-0852

ext. 7



I would call back; hopefully you talk to someone else.



Tell him you need to order some parts for the S&W M&P pistol.

Tell him you need:

Part #27798-Firing Pin Safety Plungers

Part #27766-Sears
 
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