Hi, I have a buddies 4006, he isnt an active shooter, but the gun functioned some years back.
Now, the hammer will not fall in SA use. Just like when a magazine has not been inserted. Two factory mags, neither solve the problem. Even holding up on the bottom, nada.
DA seems to function fine.
I took the grips and slide off, the trigger bar appears to activate the sear, yet not totally. And the disconnect is floating NO Constant Spring tension, which I thought was sop on semi auto pistols. Yet I cant see what would cause tension.
Now the head scratcher, With mag inserted, pressing down the muzzle, and unlocking the slide rearward, perhaps 1/16 an inch, the hammer will then drop in SA mode. No way in hades should the hammer drop with the slide out of battery!
As well, holding the trigger back and slipping the hammer from under the thumb, the sear seems to clear, I.E. like fanning a single action army revolver.
I have doucched it with break cleaner, studied the parts breakdown, I can trouble shoot 1911s from across the room and over the phone. I have 40 years of gunsmithing, its embarrassing to have to ask for help.
WTH Is out of time on this? Disconnecter? Mag safety gone south? What am I overlooking?

Thanks, Ron

With the slide removed, if you push down on the top of the disconnector and release, does it come back up on it's own? Can you feel that it is under tension....or wants to come up when you release it? Does the SA work with the slide off?

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Ret. LE, FA Instr, S&W Armorer

neither one, no tension on the disconnect, nor does the hammer drop with slide off.
been looking at this thing on the bench for a week my mind is blank on what I am not seeing.
I don't think I have ever seen any pistol with a floating disconnect, but the CRS is kicking in more and more.
as I recall the Smith DA won't fire with the slide off anyway.
And there's no "story" that would explain why it's doing hat its doing.
Of course guys lie all the time about what actually happened but this owner is a long time friend
Of course that doesn't mean his kid took it apart "to clean it" is the usual story as you well know.
Thanks keep thinking about it, I certainly am
Ron

You won't find a spring in contact with the disconnector. The drawbar spring and plunger push the drawbar back to keep upward pressure on the disconnector. If you puh down on the disconnector and there is little to no tension look at the drawbar spring to see if it has been shortened in an attempt to reduce DA trigger pull weight.

The problem probably lies in the trigger plunger spring and plunger, or the drawbar plunger and spring. Located in the trigger body, this plunger holds the trigger pin in place, and along with the drawbar spring/plunger assy keeps the drawbar it in the correct position as it is moved forward and back by the trigger's motion. The trigger plunger, and or the spring sometimes gets oxidized, and will not move up and down properly.

Check that the drawbar is free and the drawbar spring and plunger (in the frame cavity), and the trigger spring and plunger (inside the trigger body) are doing their job. Check for any restriction a movement of the drawbar itself. With the slide and grips off of the frame, pull down on the drawbar by reaching through the frame openings on either side of the magazine well. The drawbar should return fully upward when it is pulled down and released. While you have the trigger out, check the trigger plunger motion by using a non-marring tool to press down on the plunger itself. The plunger should be difficult to push down, but should move up and down inside the cavity freely.

If this plunger is moving up and down properly, and the drawbar spring and plunger, are unaltered, and the frame cavity is clean, there is probably a problem with the drawbar itself, perhaps a burr, or some hardened lubricant or shooting debris in the frame cutout that the drawbar rides in. With all the other parts out of the gun, the drawbar should slide freely back and forth in the cavity. Trigger hooks at the top of the trigger should also be checked for damage, and that the end of the drawbar moves freely in the cavity in between the hooks at the top of the trigger.

Also, while you're at it, check the disconnector itself for burrs, and check the disconnector cavity.

__________________
Ret. LE, FA Instr, S&W Armorer

thanks folks, these last two suggestions at least sound logical and give a hint of the blood trail to investigate
i will look there closer
Ron