Mainspring and Trigger Reset Problem

[Reuben948]

I have a Model 686 Plus - Noticed that I was having trouble cocking the hammer back. Gunsmith advised the mainspring strain screw had apparently loosened, and he readjusted. So now the hammer cocked back fine but I felt the trigger reset was weak, and in fact, did not reset twice during some dry firing some 200 trigger pulls.

So with a little experimentation, I tightened the strain screw fully and noticed that the trigger was not resetting much more frequently. Loosening up the strain screw, the trigger reset seems to be better, but I can't loosen it too much because the hammer won't cock and I would risk light primer strikes I guess.

Shouldn't that strain screw be fully tightened, and if so, why is my trigger binding up on the reset? Any ideas?

 

[158Grain]

The strain screw should be fully tightened. If it is loose at all you risk light strikes. As to why the trigger is not resetting, is the trigger not moving forward at all? Are you the original owner, and have you ever had the sideplate off? I'm sure others will be along much more knowledgable than me in the matter. Maybe a broken or bent hand

 

[Reuben948]

I am the original owner. The trigger resets weakly, sometimes returns half way or so - you can feel it binding, rubbing as it returns. I can free it by shaking or lightly tapping the gun. Now that you mention it, the gunsmith said he had to replace a part that was broken which he said resulted from the mainspring issue. So yes, I imagine the side plate was removed. I think I need to bring it back to him.

 

[chief38]

Either you have a broken, shortened, or weak rebound spring or there is some serious binding going on inside the gun. I obviously can not see it from here but these problems usually turn out to be a simple fix after being diagnosed. If there is binding going on the scrape marks will be your tell tale. A good GS should be able to correct this 1,2,3.

 

[snubbiefan]

What he said....has to be a trigger rebound issue. Spring, slide, rub, bind or burr.

 

[shawn mccarver]

You say you are the original owner. Are you sure of that? Did you buy it from a reputable dealer or at a gun show? The reason I ask is that it is not unheard of for a dealer to lighten the strain screw so that customers are tricked into thinking it has a "super premium action" straight from the factory, etc. Some "gun show dealers" have been known to "test fire" their "new" revolvers (what that really means is the dealer used it extensively before putting it up for sale, but it is still "new" in the mind of the unscrupulous dealer because it has never been "booked out"). In the course of that use, the dealer did a "kitchen table" gunsmith "trigger job" by backing out the mainspring and clipping a few coils off the rebound spring. I hope this is not the case, but S&W does not ship their revolvers with half-tightened strain screws, and if screwed all the way down, they simply do not loosen or back out on their own under normal use circumstances. Hopefully, you did not have a real "wanna be" gunsmith who shortened the strain screw.

The easiest fix here is a factory fresh rebound spring with a fully tightened strain screw. If there is still a binding which causes the trigger to fail to return, then it should go off to S&W.

 

[Reuben948]

It's a brand new gun from a reputable dealer I have known for many years. I have no doubt that the strain screw backed out during use and lead to the cocking problems which are now repaired. He tightened it, but I was able to tighten it an extra quarter turn while I was investigating the trigger reset problem. This increased the binding ever so slightly, but it was there since the repair so that is not the direct cause. I know the gunsmith replaced a part, as he told me he did, but I don't know what that part was. I will bring it back to him Monday and post what the result was. It fired today without problem but the trigger reset was very slow and did not return fully once out of 28 shots. My guess is that something is binding, but we shall see....

Thank you all.

 

[Reuben948]

It was the trigger rebound spring, replaced in a couple minutes and it works fine now. Thank you all very much

 

[Hapworth]

It was the trigger rebound spring, replaced in a couple minutes and it works fine now. Thank you all very much

What was wrong with the spring?

 

[hotrod150]

....the gunsmith said he had to replace a part that was broken which he said resulted from the mainspring issue.......

I'm curious which part this was? I'm no expert, but I can't really think of what part might fail due to a loose strain screw. Maybe someone had shortened the strain screw itself and he replaced that?

 

[Reuben948]

I don't know what was wrong with the spring, or what part he had to replace. He's done a lot of repairs for me over the years, if he see's something that is questionable he replaces it.

The trigger was scratchy from day one out of the box, then the cocking problem. It's actually working quite nicely now. Not smooth as glass but smoother than it was when it was new. The strain screw is tight, it cocks nicely. the trigger is consistent, and the reset is acceptable.

Right now, I am real happy with it.

 

[Hapworth]

I don't know what was wrong with the spring, or what part he had to replace. He's done a lot of repairs for me over the years, if he see's something that is questionable he replaces it.

The trigger was scratchy from day one out of the box, then the cocking problem. It's actually working quite nicely now. Not smooth as glass but smoother than it was when it was new. The strain screw is tight, it cocks nicely. the trigger is consistent, and the reset is acceptable.

Right now, I am real happy with it.

Then case closed and a happy conclusion -- excellent.

And welcome to the Forum, but the way...