Pictures Of Sigma Internals?

[Kawabuggy]

I took my Sigma apart yesterday to clean it. I got carried away and decided to implement some trigger updates. I did some light polishing, swapped one of the sear springs and put it back together. Noticeable difference as the trigger is much lighter than before-BUT-I have a problem wherein the the top sear pin (the one the trigger rod pushes on) keeps falling out after repeated dry-firing of the gun. I can pull it back down and see that the top pin is physically coming out of the holes in the sear bracket. I swapped back to the factory dual spring set up, and yet the problem continues. Anybody have any ideas as to why this might be happening? There is nothing to physically hold that pin in place. Perhaps when I opened it up, there was something there and it fell out and I did not see it fall?

Otherwise, I have studied it very carefully, and cannot see what would hold it in place. I could modify the trigger rod to include a tab (tig weld) but maybe there is something obvious I am missing. If someone has a picture of their gun with the slide removed, I would very much appreciate seeing it.

Also, I see that a lot of posts state that there has not been much success at modifying the triggers in the Sigmas and yet Midway sells different springs just for this purpose???? Should I just leave it as the factory intended-or is it really possible to modify the pull? If it matters-I have successfully modified the trigger in several other guns I own. Some with more success (lighter pull, less creep) than others, but still I have achieved a level of success with each & every one. Why not the Sigma?

 

[Kawabuggy]

I took my Sigma apart yesterday to clean it. I got carried away and decided to implement some trigger updates. I did some light polishing, swapped one of the sear springs and put it back together. Noticeable difference as the trigger is much lighter than before-BUT-I have a problem wherein the the top sear pin (the one the trigger rod pushes on) keeps falling out after repeated dry-firing of the gun. I can pull it back down and see that the top pin is physically coming out of the holes in the sear bracket. I swapped back to the factory dual spring set up, and yet the problem continues. Anybody have any ideas as to why this might be happening? There is nothing to physically hold that pin in place. Perhaps when I opened it up, there was something there and it fell out and I did not see it fall?

Otherwise, I have studied it very carefully, and cannot see what would hold it in place. I could modify the trigger rod to include a tab (tig weld) but maybe there is something obvious I am missing. If someone has a picture of their gun with the slide removed, I would very much appreciate seeing it.

Also, I see that a lot of posts state that there has not been much success at modifying the triggers in the Sigmas and yet Midway sells different springs just for this purpose???? Should I just leave it as the factory intended-or is it really possible to modify the pull? If it matters-I have successfully modified the trigger in several other guns I own. Some with more success (lighter pull, less creep) than others, but still I have achieved a level of success with each & every one. Why not the Sigma?

 

[chicky77]

i believe the upper sear pin can only go in/out one way. if it were to fall out it would fall toward the inside of the frame.it should be held from falling out by the sear ramp assembly. I'd check to make sure you did'nt mix up the upper/lower pin.

 

[bigal_2482]

hope this helps

 

[Kawabuggy]

You are correct that the pin only goes in one way. It is a "stepped" pin meaning one end is smaller in diameter than the other end. Therefore, it only goes in one way-you cannot put it in backwards-you were right about that. It is in the right hole as well because if you put it in the bottom hole-the trigger rod can't be connected.

You indicate that the "sear ramp" may hold it in-what exactly is the sear ramp?????

If it matters, I can duplicate the problem with the slide removed. There is pressure on the sear when the gun is cocked (usually hammer pushes the sear towards the barrel of the gun) this releases the pressure on the top pin, and allows it to fall out. When not in the cocked position there is tension on the top pin and it can't come out. I can't see any type of retention system for this pin-and am wondering if something fell out when I was taking it apart. If anyone has a picture-please post it up! Otherwise, I will tig weld a small tab to prevent the pin from backing out-but still allow removal when/if necessary in the future.

I don't understand why S&W attempted (they missed the mark) to make it as complicated as it is. I could achieve BETTER results, with half the moving parts that they have used, and it would be of higher quality and have greater durability. The cam design of the sear riding on plastic is NOT designed for long term usage. Further, the fact that the cam portion of the sear is not finished well and is very rough will guarantee that the plastic wears over time. I have only put 150 rounds through mine and already there are witness marks & scratches on the plastic where the sear rides.

 

[Kawabuggy]

Thanks for the illustration. I found that last night as well. Item 12 is what I am working on but you CAN'T SEE ANYTHING IMPORTANT in that illustration. It does not show the pin in question, nor does it show any type of retention for that pin. The illustration does not go into the sear assembly-which is what I really need.

 

[Kawabuggy]

Solved it. Chicky77 was right about the pin being in backwards.. Well actually, I had the entire sear bracket in backwards which allowed the pin to walk out. Once I flipped everything over-the pin is now trapped against the sear ramp! Thanks for the very fast responses!

Since I got the pin figured out, I went ahead and removed the outter sear spring. Did not seem to make much difference. Seems like it is still pretty stiff. Can anyone else offer any additional suggestions on how to make the trigger softer? What about changing the trigger return spring? I would have to guess that it is adding at least 3 lbs. if not more to the pull.

 

[LuddhaBuddha]

Did you remove the pigtail spring, I took it off and that helped a little. I also took out the outter coil spring you mentioned but it caused the gun to fail to cock about 20% of the time while firing so I put it back.

 

[Kawabuggy]

This is what I can tell you that I have done that has worked very well to reduce trigger pull-I ACCIDENTALLY put the sear bracket into the plastic sear ramp BACKWARDS. Believe it or not, just doing this one simple thing made the trigger much easier to pull! Even with the pig-tail spring in place, and both springs on the sear-it was a lot easier to pull the trigger! Geometry change? Regardless, with the sear bracket in backwards-the top pin, the one the trigger rod pushes on-can walk out of the sear bracket and render the fire-arm unable to fire. Can't have that.

I pulled it back apart and put the sear bracket in the correct way, left out the pig-tail spring, and the outter sear spring-and the trigger is exactly like it was from the factory-no difference. Too hard.

If I can come up with a way to retain the top pin, with the sear bracket in backwards-even with all of the factory springs-it is MUCH easier to pull, and this would be ideal.

Instead of going through all of that trouble, I am going to first buy a softer trigger return spring from Mid-Way to see how much that helps. If it does not make a considerable difference-I will then come up with a way to retain the pin with the sear bracket in backwards as this really made a significant difference.

 

[gmchenry]

There are ways to make the trigger pull lighter, but I've yet to see any of those modifications that didn't come at the expense of reliability.

Smoothing some of the machine marks from parts with 1500 grit will help make the trigger pull smoother. The heaviness doesn't bother me, but the trigger pull has to be smooth.

 

[Kawabuggy]

I am looking for more than just a smoother trigger pull. To satisfy me it will have to be MUCH lighter, have reduced travel, and ZERO creep.

To reduce travel, I am going to weld up the slot in the trigger rod that pushes the sear pin. Then I am going to create a new slot that is very close in diameter to the pin-instead of having a HUGE slot that pushes on a tiny pin as it is from the factory! That should take out the free travel.

Next, I am going to modify the sear ramp so that it can sit lower in the housing. This will reduce creep. I will have to go a little at a time until I reach the magic spot.

I have already polished my sear where it contacts the ramp, and where it contacts the hammer. I also polished the hammer and edges where the sear & hammer meet to allow a smoother release.

I am still working on lightening the pull though. I have a trigger return spring kit coming from Mid-Way. Once that gets here, I will see how different the lighter springs will make it. If that does not do the trick, I will flip the sear bracket back over-and weld a tab to hold the top sear pin in place as I KNOW this significantly lightens the trigger pull.

 

[gmchenry]

Originally posted by Kawabuggy:
I am looking for more than just a smoother trigger pull. To satisfy me it will have to be MUCH lighter, have reduced travel, and ZERO creep.

Then get a different pistol.

 

[Kawabuggy]

Gm, while I appreciate the advise, I must tell you that I am the type of person who actually enjoys tinkering with things. I'm sure that I will be able to find my "shang-ri-lai" after a bit of searching.

Perhaps once I have proven that this can be done, others will follow. Or, I might finally give up and throw my hands in the air and say "you got me". Either way, it will be documented here for others and they won't have to walk in my shoes to know what I know.

Either way, this journey is like life in that it is all about the "trip" and not so much about the destination. Would be nice to have it my way, but if that does not happen I'll still be content in knowing I gave it my all!

 

[ArgMauser]

More power to you, Kawabuggy. Should be an interesting journey. Best wishes.

 

[99Mustang]

Kawa,

I also performed my own trigger work after having recently bought a 9VE. I used many of the suggestions on this site and others (trimmed springs, polished sliding sufaces). The pull is now much lighter than stock (about 5 to 6#). The biggest improvement is how smooth the pull is compared to stock (stock was AWFUL). I found that polishing the inside of the slot in the sear block made the most difference in smoothness.

I don't currently have a tool that can fit well in the slot so I'm not done. FYI, I used a hex key in the slot and tried to smooth down the slot. I was able to smooth out the high spots, but think I can do better.

As for Sigmas, for the price, it makes a good defense gun with a large capacity mag to boot. I don't think the design lends itself to ever becoming a target/competition gun, but with a little bit of elbow grease and time, you can definitely improve the trigger. Good luck on your "trip".

 

[Kawabuggy]

Mustang, I thought about polishing the inside of the sear like you did but then realized that doing so will actually add more slop to the pull. I think if given the choice, I would polish the inside uniformly from one end to the other, and then drill the sear bracket for a bigger pin to take up the extra clearance.

I just got the spring kit in from Midway and they are NOT THE RIGHT SPRINGS! For anyone else that reads this-Midway does not have the right springs for this gun! They say they used to carry the spring kit-but that it has been discontinued and they do not have a replacement kit at this time. Unfortunately, I learned this the hard way after disassembling the slide/firing pin assembly only to learn that these springs WILL NEVER WORK. Midway says-sure you can mail them back. Thanks Midway! That is very kind of you!

On their web site it lists Wolff Trigger Return Spring Pack S&W Semi-Automatics> Product #487099

I am still waiting on the Wolff Striker Spring for Sigma Product #295637. Since the name of my gun actually appears in the description, I am hoping that it will work in this gun.

 

[Kawabuggy]

Okay, here is the update. The striker spring came in, and it has made a very big difference.
I installed the spring, did some more polishing to the inside of the sear where the trigger push pin moves the sear (as 99mustang) suggested, and that seems to have helped as well. The gun is a night & day difference now as compared to what it was like when new. I would highly recommend this as a standard update with these guns.

There are still some other things I would like to do to reduce the amount of free play, and that will come in time. Have to break out the TIG welder to get that done.

 

[99Mustang]

Kawa,

I didn't notice any more slop when I cleaned out the slot in the sear, but mine could have been tighter to begin with. When I did the polish work, I actually did the rest of the sear block but not the slot. I re-installed it and while there was a slight improvement, it was still very "sticky" and rough. Only after I tried to knock off the rough spots on the sear slot did I get a significant improvement, the trigger is much smoother.

I still plan to revisit the slot as I feel I could do a better job of polishing it, but have to figure out a tool to use that will fit the slot and not take too much metal off. For now the trigger is vastly improved from when I bought it.

FYI, it was because of the bad trigger that I found this forum, so that's one positive thing about my experience with the Sigma.

 

[Kawabuggy]

99 mustang-I agree with you that polishing the inside of the sear did not add significantly more slop, but there was too much slop there from the factory to begin with. I think later I will weld up the slot in the trigger push rod where the sear pin rides. By tightening up that slot, the sear will begin to move as soon as the trigger moves. That is the extra slop that I want to remove. If you look at the slot in the trigger push rod, you will note that the sear pin is about 1/3 the size of the slot. Should not be that way.

I would say that polishing the sear slot definitely made the pull smoother. Before it felt like the trigger would start to pull, then bind up, then move again. It was not a smooth steady pull before. Now with the sear slot polished it feels like it is a more steady pull with little binding.

The striker spring made the biggest difference in the tension required to pull the trigger.

In case anyone is wondering I had only 1 FTF last night out of 150 rounds. There was a small ding in the primer but the shell did not fire. I put it back in the clip, loaded it again, and it fired the 2nd time. The other 149 rds. when BANG on the first pull.

I let the guy that works the counter at the shooting range dry fire my pistol. He said he was very impressed with the work. I can't say enough about how much better this pistol is now with the changes.

I hope this has been of some benefit to anyone else considering doing this. It is well worth the time to sort the trigger out. You don't have to live with it the way that it is. I have minimal $ investment so far. I think I have spent $9.31 on the striker spring. And about 2 hours polishing everything, and figuring out how it all goes back together. Otherwise, about 1 hour to polish everything if you have a better memory than me.

 

[Sultan]

I went to the Wolff Gunsprings website and they don't show either one of those numbers now for the Sigma 40VE. Am I missing something here? I love the weapon and it is very accurate, but I'm going to have to come up with a solution for the spring pull weight for me to enjoy shooting it. I'm leaning very heavily towards Mustang's suggestions at this point.

Also, can someone tell me how to get the plastic retainer off the back of the slide without breaking it? I wanted to polish the items in there that have been mentioned.