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Discussion Starter · #1 ·
I've read several descriptions of the trigger job performed by people. Mostly it involved lapping the surfaces of the mating areas to make them smooth. I guess those are the areas (A) on the trigger and (H) on the hammer.

When I pull the trigger, I do feel some "grinding" that indicates the surfaces are rough, and lapping them would make trigger pull smooother - which is a nice thing.

1. The trigger is pulled, against the resistance of the trigger spring and friction of the surface (A) which slides to the right over the surface (H).

2. Just before surface (A) is ready to slip off and release the hammer, the surface © of the sear - which is moving together with the trigger because of the sear spring - comes into contact with the surface (F) of the hammer and does not let trigger move further. I guess that concludes the first stage of the two-stage operation.

3. With increased pressure on the trigger - now against the resistance of compressing sear spring, in addition to the trigger spring and friction of the surfacres, the trigger moves further to the right while the sear stays still, untill the surface (A) finally slips off the surface (H) and the hammer is released and moves up with surfaces © and (F) grinding. I guess lapping the surfaces © and (F) could make that motion smoother and more consistent too.

I do not understand how smoothing the surfaces in question - (A) and (H) - would considerably reduce the trigger pull weight. The friction cannot be that great, compared to the resistance of the sear spring and trigger spring combined, can it?

It would seem that only cutting off a piece of the the sear spring would reduce the trigger weight of the second stage. But all accounts indicate lapping sufficient to bring the weight down considerably.

Any thoughts?

V.
 

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"V", your reasoning is in agreement with mine--thats why I cut about 1 coil off that little itty bitty spring in addition to stoning the mating surfaces. Pull is smooth, letoff a little "spongy" (hardly like a Timney trigger) but a considerable improvement over what it was. I'm not a fan of two stage triggers but with a semi auto find it to be a safety factor.:usa: :ar15:
 

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Discussion Starter · #4 ·
Billc,
Could you describe a "stoning" process please.
Also, how hard is it to disassemble and re-assemble the parts in order to get to that sear spring.

V.
 

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"V". I had good success on pistol sears using white colored India Stones. Very, very fine. Using those under magnification you can remove the roughness from the touching surfaces without changing the relationships between them. Improvement is noticable as you go along. As long as the relationships are not changed you can only do positive things. With a courser stone you must be very careful not to remove too much--objective to polish not reshape.

The two larger springs are under preload so watch as you remove them (no boinging!!!). Once removed you will see how to further disassemble. It doesn't take much removal from the smallest spring to make a significant difference on the trigger pull--take care!!

Hope this helps.....:) :usa: :ar15:
 

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The friction between A & H is like the friction to snap your fingers. (thumb & middle finger) I apply a dab of gunslick there once in a while to keep it smooth. Mike knifong did my trigger job.

I think there is more to it than laping A & H. A reduced trigger spring wt. would help.

Brownells, has an adjustable trigger, at $79 its a bit high for my budget. Check out: http://www.brownells.com/aspx/NS/store/Pro...tail.aspx?p=167
 

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Originally posted by Billc
"V". I had good success on pistol sears using white colored India Stones. Very, very fine. Using those under magnification you can remove the roughness from the touching surfaces without changing the relationships between them. Improvement is noticable as you go along. As long as the relationships are not changed you can only do positive things. With a courser stone you must be very careful not to remove too much--objective to polish not reshape.

Hey Billc

Is crocus cloth fine enough to polish the sears or is the metal too hard?

The two larger springs are under preload so watch as you remove them (no boinging!!!). Once removed you will see how to further disassemble. It doesn't take much removal from the smallest spring to make a significant difference on the trigger pull--take care!!

Hope this helps.....:) :usa: :ar15:
 

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"dvdstdg" Hi. #1500 Wet or dry would be better provided you had a way to avoid any slack or play when applying to the work surface. What I have done with a degree of success is put the wet or dry on a piece of glass at the edge and, holding the part in hand, moved it over the smoothing surface. The advantage of using a stone is the rigidity and precise 90 deg angle so no rounding occurs with the polishing , back/forth movement.
Using a "stroke" instead of "rubbing" helps to keep a true surface. If you try to fold the paper over or around the edge of the glass you will remove material you didn't want to remove due to the increased radius at the edge. Careful is the word! It may be more economic to pay Mike rather than buy more parts from Ruger/Supplier. Hope this helps in your decision. Best, Bill :usa: :ar15:
 

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Originally posted by Billc
"V". I had good success on pistol sears using white colored India Stones. Very, very fine. Using those under magnification you can remove the roughness from the touching surfaces without changing the relationships between them. Improvement is noticable as you go along. As long as the relationships are not changed you can only do positive things. With a courser stone you must be very careful not to remove too much--objective to polish not reshape.

The two larger springs are under preload so watch as you remove them (no boinging!!!). Once removed you will see how to further disassemble. It doesn't take much removal from the smallest spring to make a significant difference on the trigger pull--take care!!

Hope this helps.....:) :usa: :ar15:
[How much do you cut off of the sear spring?
 

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Hi. I polished sear and cut spring at the same time. I removed one full circle from the spring and it was just right. Disassy/assy of trigger group is a pain, but one at a time would reduce the chance of taking off too much.

Overall result is a very smooth 2 stage (with initial stage so smooth you really can barely tell its just not slack) and a safe letoff. Have had no involuntary double taps so it is predictable.
:D :usa: :ar15:
 
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