Anyone know exactly where to polish on a SIG to slick up the DA trigger?  I have mine stripped down, at least as far as I can (how the F do you get the trigger/trigger bar out?) and it isn't really clear to me what needs polishing.

Thanks!
QS

IMHO there’s not too much you can do to a Sig trigger because of how it is designed.  

If you’re determined to work on it, just look for wear points and polish them slightly.  The parts are probably case-hardened, which means if you take off too much, you’ll be down to soft metal.  Don’t change any angles.  Very lightly stoning parts that rub together may help, but you’re just trying to remove burrs, nothing more.  Remember that stoning parts is the equivalent of adding wear to those parts.

Removing the trigger bar is a bit tricky.  However, it does NOT require any force at all.  

When removing the trigger bar/trigger assembly, use the forefinger and thumb of one hand to manipulate the trigger while using the forefinger and thumb of the other hand to manipulate the rear of the triggerbar.

See the pictures below.  In the left photo, the rear end of the trigger bar is still sitting on a shelf in the frame.  Note how the bottom of the trigger is to the rear, the top of the trigger (not visible) is forward.

In the center photo, the top of the trigger has been moved forward even more while being twisted toward the left side of the gun, the rear end of the triggerbar has fallen off the shelf.  Note how the bottom part of the trigger is twisted toward the camera.  The triggerbar/trigger assembly is ready to simply fall out.

The right photo shows the same thing as the center photo, but from the top of the frame with the gun pointing in the opposite direction.

When disassembling, hold the gun with the left side down and the triggerbar will fall out of its groove in the frame.  When reassembling, hold the gun with the right side down and the triggerbar will fall into its groove in the frame.



Reminder:  The trigger return spring goes in the notch in the triggerbar, not the hole.  Also, if you remove the magazine catch, make sure you reinsert the small spring-loaded detent correctly.  Otherwise you can’t take it apart again.  (I’ve seen this happen to a number of Sigs – the solution is to drill out the mag catch.)

Good luck – take your time – don’t force anything.

Thank you!! I couldn't get an answer on the SIG forums other than "send it to Teddy Jacobson."  

I started polishing with felt and 1200 grit valve lapping compound last night.  I did the right side of the trigger bar where it bears against the frame, as well as starting to polish the area on the hammer directly above the safety intercept notch.  It looks to me like the sear bears against this area during the initial part of the DA pull, and maybe it's responsible for a little of the roughness I can feel.  Please correct me if I'm wrong.

The initial problem that prompted me was the fact that this 228 (purchased used in 99% condition)  would misfire about 2-3x per 100 rounds.  The primer strike was too light, IMHO, and it appears someone has installed an aftermarket spring.  I ordered a 20 and 22# spring from Wolff yesterday, as I believe the spring that came in the gun is about 16#, way below the factory 24#.  

Thanks again.

QS

Quiteshooter:

Please don’t get carried away with this!!

I doubt the sear is causing much of a problem with the DA triggerpull.  Trip the sear spring to relieve the pressure against the hammer and see if that changes anything (simply use a small screwdriver to push the sear spring leg off the short pin coming through the ejector).

A few additional suggestions:

Keep the valve-grinding compound away from the aluminum frame – it can become embedded.

Working on a $15 part like the trigger bar is OK – working on a $300 part like the frame is not.  (I just made up that amount OBTW, Sig frames aren’t available separately – so if you ruin the frame, you’ve ruined the gun.)

As I'm sure you know, the aluminum frame has a hard, slick outer coat called anodizing.  If you accidentally remove that, you’re down to soft aluminum, which will wear fast (and isn’t very slick).

Trigger work is best done with stones, like you get from www.brownells.com.  Stones keep surfaces flat and make it easy to maintain angles, plus they’re great for just cutting burrs and nothing else.

Don’t forget to consider the mainspring assembly as a source of roughness.  Remove it, use thumb pressure against the hammer to emulate mainspring pressure, and see if that does anything.

Stay away from the tab at the center top of the triggerbar.  That’s the disconnector.  (OK, if it’s rough maybe a single, light pass with a stone is acceptable – nothing more.)  

Incidentally, the disconnector will eventually whack a groove in the bottom right edge of the slide.  This is normal, don’t worry about it.  Once the groove gets really ratty looking, you can stone it down ever so slightly to remove any raised edges.

Also, the rearmost top tab on the rear end of the triggerbar may wear a gouge in the frame shelf that I referred to in my first post.  This tab rides along the bottom of the hammer pin and is clearly visible in the first two photos, above.  

Sometimes the rear, frame side edge of this tab is a little sharp and starts shaving the shelf a bit as the trigger is released.  If it looks like this edge is sharp, just kiss it with a stone to round it.  Also, keep this area lubricated.  

Keep in mind that as you use the pistol, the trigger will wear in a bit anyway, and become smoother.  Also, a really good lubricant such as Brownell’s Action Lube Plus grease (applied with a toothpick to wear surfaces) can really smooth out a trigger.  

If you have any intention of using this firearm for personal protection, it needs a full strength mainspring – period, end of story.  If you ever have to point this thing at someone who is trying to harm you and pull the trigger, it had better go off!!  Nothing is more important than this, plus in this event you won’t even notice how light, heavy, smooth, gritty or whatever that the trigger is.  

Good luck again.  Go slow – and recognize that the Sig is designed as a military, not competition, firearm.

Quoted: Quiteshooter: Please don’t get carried away with this!!

Not to worry...I have enough experience with light gunsmithing to know when to quit. :-)

I doubt the sear is causing much of a problem with the DA triggerpull.

True.  I did nothing to the sear.  

A few additional suggestions: Keep the valve-grinding compound away from the aluminum frame – it can become embedded.

Didn't touch the frame at all.  I flushed the parts with Gun Scrubber before I relubricated them with Brownells Moly-Slide.

Trigger work is best done with stones, like you get from www.brownells.com.  Stones keep surfaces flat and make it easy to maintain angles, plus they’re great for just cutting burrs and nothing else.

I did the following:  polish to mirror finish the right side of trigger bar where it rides against the frame, polish edges and just a kiss with felt and rouge on the disconnect tab on trigger bar.  I polished the hammer where the sear bears against it (above the safety intercept notch) as well as polishing both sides of the safety lever.  Then, I polished the mainspring leg.  

Don’t forget to consider the mainspring assembly as a source of roughness.  Remove it, use thumb pressure against the hammer to emulate mainspring pressure, and see if that does anything.

It was gritty.  I put a shine on the spring strut.

Keep in mind that as you use the pistol, the trigger will wear in a bit anyway, and become smoother.  Also, a really good lubricant such as Brownell’s Action Lube Plus grease (applied with a toothpick to wear surfaces) can really smooth out a trigger.

I use the Brownells Moly-Slide.  Slicker than snot on a doorknob, and it burnishes in after a while.

If you have any intention of using this firearm for personal protection, it needs a full strength mainspring – period, end of story.  If you ever have to point this thing at someone who is trying to harm you and pull the trigger, it had better go off!!  Nothing is more important than this, plus in this event you won’t even notice how light, heavy, smooth, gritty or whatever that the trigger is.   Good luck again.  Go slow – and recognize that the Sig is designed as a military, not competition, firearm.

My feelings exactly...that's why I was so pissed when it misfired.  It is a fighting/carry piece, I don't have any intention of making it into a bastardized match gun.  

I haven't completely reassembled it yet, and won't until I get my new mainspring from Wolff.  Just applying thumb pressure to the hammer, it's measurably slicker.  I think I'll be happy with it, as long as it quits with the misfiring.

I'll report back after I assemble it and testfire.

Thank you very much for your help!

QS