I just recently replaced all the springs in my Model 469 (Wolff Springs Service Pak), and after reassembly the pistol functioned perfectly. I fired 3 magazines worth of ammo through it with no malfunctions. Today, as I was doing some dry fire drills, I noticed that every once in awhile (like once in 12-15 times) when I pulled the trigger the hammer would catch at the half-cock instead of falling completely. It desn't seem to do it at all when I slowly pull the trigger, and like I said before, when it does happen it's not very often. This only happens in double action - when I fire single action it seems fine. Any ideas? I tried calling Smith & Wesson today, but the wait on hold was longer than I had to devote to this issue (although I did like the big band music they had playing).

Does the service pack kit have multiple main spring weights like the calibration pack?

If it did, you could have too light of a hammer main spring installed.

I had the exact same issue on a 1076, when I sent it back to S&W, all that was done to fix it was a new mainspring.

Another forum member had the same problem with his M39-2, I suggested changing the mainspring and it fixed the problem for him too.

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Conrad
SWCA #1830 SWHF #222

Cool! There was only the one mainspring, but since I wasn't having this problem before, I'll just replace the mainspring with the one I removed and see if that doesn't solve the problem. Once again the Forum comes through for me! Thanks!

I had the exact same problem with my 559 when I replaced the springs.

You stated you replaced "all" the springs so I am assuming you also replaced the trigger return spring as well.

When I replaced the stock springs I utilized a 2.5# trigger spring and a 16# hammer spring.

My pistol then had the symptoms you described. Sometimes the hammer would fall to the half cocked position during double action firing.

In my pistol it was caused by the 2.5# trigger return spring. When I replaced the 2.5# with a 3.5# trigger spring it corrected the problem. The 2.5# spring worked just fine in single action mode.

I have had no problems with the 16# hammer spring.

Thanks azredleg - I switched back the mainspring, and the problem persists. That'll be my next step.

FLYGUY

There was a recall on the 469. Obviously, with gun empty, slowly pull trigger back in DA mode. When you hear click (hammer back about 3/8 inch) stop trigger pull. Depress decocklng lever. If hammer does not fall to slide, it is in the recall

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Bill
Dis B. Leaf

Only in DA, right?

If the drawbar plunger spring is too light, it can cause a Skips-DA condition to occur (hammer falls too soon in DA).

The drawbar plunger spring (Wolff calls this a trigger return spring) must have enough tension to lift the tail of the drawbar up under the hammer so it engages the hammer's DA pick-up notch and the Throw notch. If the tension is too light, the drawbar may not lift up and fully engage the hammer ... and the hammer may drop off the drawbar before it can be pulled all the way back (where it's intended to be released to fall by its throw notch camming off the tail of the drawbar).

This can also result in light strikes and failures-to-fire in DA mode during live-fire.

You'll note the Wolff website states: WARNING: Springs are for competition use only - NOT for duty use.

If use of the stock factory drawbar plunger spring doesn't restore normal DA functioning, then the gun needs to be examined by the factory or a gunsmith familiar with S&W pistols, as the hammer and/or drawbar might require replacement due to worn/damaged notches.

Obviously, I have no way of knowing what's happening with your pistol, but a light drawbar plunger spring can easily fail to keep the drawbar tail properly tensioned, which can cause the hammer to fall off the drawbar too soon.

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Ret LE Firearms inst & armorer

Thanks to all for the input - RE: recall - when I first aquired the pistol, I checked both serial # and function checked it, and mine isn't one of the recall pistols. This may necessitate a call to S&W for a proper look-over by one of their gunsmiths, since swapping out the springs hasn't entirely solved the problem.

You didn't mention if you changed the grips or not, but I had a set of grips that had a small piece of flashing that was touching the drawbar and causing the same issue. You may want to check that out even if you haven't changed grips, you must have removed them to change the mainspring, it does not take much interference on the drawbar to cause a problem....

I had the same problem with my 639s.The pistols have a firing pin safety so the half cock is superfluous. I change mine to 3rd gen hammers and the problem was over. The DA pull was much better than it was about as good as my Sigs but not close to my Berettas or Czs. Now how to smooth out the DA pull??? After read more than a few threads here on the better engineering of the MIM hammers on the last of the Gen3s I figured I would give one a try. To say I was impressed with the DA pull would be an understatement . My transition drills are now fun not frustrating . I will most likely put a MIM hammer on my 5904 and see what it does for it.

Okay - here's the punchline. It would appear that the problem has resolved itself. No idea why, but then I had no idea why it did it in the first place. Anyway, after a bunch of DA dry-firing and a trip to the range today, I remain cautiously optomistic.
On the subject of a 3rd gen MIM hammer - I had considered that, and may in the future do the swap, if I stumble across a good deal on a hammer. Anyway, thanks to all for the input - the main reason I love this forum.

Update - I bought a 3rd Gen hammer assembly (MIM) and installed it - as I had hoped, problem solved. Also, as I had hoped, the DA pull is MUCH smoother. Thanks again for all the expert info. My 469 is now fully operational, and with the Pachmayr grips (stumbled across a guy on eBay with a NOS set in the box) it's a perfect fit. Here she is - definitely not a safe queen, but the perfect (for me) carry weapon.

469 Pachmayr 2.jpg