469 hammer sometimes stops at the half cock

[Borderboss]

I just got a new-to-me 469, serial TAZ89XX. When doing some dry firing, the hammer will occasionally stop at the half cock instead of falling completely. It's random, happening once in a while. For a gun I'll be using for self defense, this is not acceptable. This gun wasn't subject to the recall back in the day, and the issue of the recall was different than this.

Does this issue ring a bell for anyone? I'm hoping it's a simple fix. Thanks for the help.

 

[armorer951]

Could be an issue with shooting debris or accumulated dirt, or wear and tear on the internals, like the drawbar and the sear. Function check the disconnector to see that it is working properly.

If you are able, I would start with a thorough disassembly and cleaning of all of the parts. Use a toothbrush and your solvent of choice to scrub the internals, and inside of the frame cavity. Take a close look at each of the parts and springs for evidence of damage or abnormal wear. Wipe down the parts before re-assembly. While you're in there, replace the mainspring. If you cant find an OEM spring, Wolff has them.

I would also disassemble the slide, with the exception of the extractor, and diligently clean out the firing pin cavity and replace the firing pin spring with a new one. Do not lubricate these particular parts before re-installing them.

If you are still having this issue after cleaning and replacing the mainspring then the drawbar/sear interface is probably the culprit. The hammer could also be damaged or worn, either at the safety notch location (half cock), or on the SA bevel on the sear.

If you need help, there may be S&W armorer in your area.

 

[JohnHL]

Sometimes, when dry firing, the hammer will "bounce" back to the half-cock notch and give the impression that it has not gone fully forward.

To test for this, insert a pencil, eraser first, down the barrel and hold it lightly in place with the fingers of the non-firing hand as you dry fire the pistol.

If the hammer is striking the firing pin, you will feel the pistol attempting to launch the pencil.

If the hammer is actually stopping at the half-cock notch, you will feel nothing at the pencil.

If you conclude that the hammer is NOT striking the firing pin, armorer951's suggestions are spot-on.

John

 

[Borderboss]

Sometimes, when dry firing, the hammer will "bounce" back to the half-cock notch and give the impression that it has not gone fully forward.

To test for this, insert a pencil, eraser first, down the barrel and hold it lightly in place with the fingers of the non-firing hand as you dry fire the pistol.

If the hammer is striking the firing pin, you will feel the pistol attempting to launch the pencil.

If the hammer is actually stopping at the half-cock notch, you will feel nothing at the pencil.

If you conclude that the hammer is NOT striking the firing pin, armorer951's suggestions are spot-on.

John

The tip about holding the pencil is a good one. I just tried it one time without holding the pencil and shot the pencil across the room.

 

[armorer951]

Thanks for that tip John....I've never experienced this phenomenon of the hammer bouncing before. We used to do that "pencil projectile" trick after re-assembly sometimes, to confirm a good strong impact by the hammer............good to know there is a bench "test" for the "bounce".

 

[stansdds]

I can't say that I've ever had the hammer bounce back to the half-cock safety notch on my Model 439, 645, or the pilot version of the 4506 that I had years ago, nor the 39-2 that I had decades ago. I would think that the hammer spring would have enough pressure and length to prevent that degree of hammer bounce.

I'm thinking there may be something up with the hammer and/or sear or perhaps someone messed with them and/or the hammer spring in an attempt to get a better trigger pull.

 

[stansdds]

I just looked at the pictures of this pistol that you posted in this thread:

http://smith-wessonforum.com/140519099-post31.html

It looks to be in fantastic condition, used very little, if at all. It is possible that it left the factory with an issue between the hammer and sear, with the half-cock notch sometimes catching the sear. The milled steel parts used in some of S&W's second and early production third gen pistols often left much to be desired in terms of machining and finishing.

 

[Borderboss]

I just looked at the pictures of this pistol that you posted in this thread:

http://smith-wessonforum.com/140519099-post31.html

It looks to be in fantastic condition, used very little, if at all. It is possible that it left the factory with an issue between the hammer and sear, with the half-cock notch sometimes catching the sear. The milled steel parts used in some of S&W's second and early production third gen pistols often left much to be desired in terms of machining and finishing.

It actually is in great shape, showing very little wear. The magazines aren't S&W, not having any markings. The trigger pull is really heavy, so it's going to need some work in some manner to lighten and smoothen it up. But I really like the way this gun feels.

 

[armorer951]

I wonder if someone has substituted a different hammer at some point. None of the 669/6906 hammers I have in stock have a safety notch or step on them. Technically, it should work with a stepped hammer, but wouldn't such a notch be redundant on the 469/669?

 

[Borderboss]

I wonder if someone has substituted a different hammer at some point. None of the 669/6906 hammers I have in stock have a safety notch or step on them. Technically, it should work with a stepped hammer, but wouldn't such a notch be redundant on the 469/669?

The S&W exploded view for the 469 seems to show a half-cock notch on the hammer. Of course, it's a drawing, so hard to say if it's accurate.

 

[old&slow]

Sometime ago I purchased a 39-2 and it would catch the hammer
on half cock.. I posed the question on this forum and someone ,
( sorry I don't remember who) suggested I get a new main spring
( hammer spring) . I did and it solved the problem ..

 

[Borderboss]

Sometime ago I purchased a 39-2 and it would catch the hammer
on half cock.. I posed the question on this forum and someone ,
( sorry I don't remember who) suggested I get a new main spring
( hammer spring) . I did and it solved the problem ..

That's promising! I ordered a bunch of other springs from the gun from Wolff. I think I need a few more!

 

[BLUEDOT37]

My 845 Limited does that. It didn't do it (or I didn't notice it) when I first got it.

I replaced all the common springs, including the mainspring, & it still does it.

I finally learned to not let it bother me.

.

 

[JohnHL]

I wonder if someone has substituted a different hammer at some point. None of the 669/6906 hammers I have in stock have a safety notch or step on them. Technically, it should work with a stepped hammer, but wouldn't such a notch be redundant on the 469/669?

Yes.

The firing pin safety, first installed on the 2nd gen models did make the half-cock or safety notch redundant.

Back in the day, S&W got a lot of criticism regarding the double action trigger pull because the half-cock notch can be felt as it drags across the sear.

The 2nd gen models had them but they were discontinued on the 3rd gen.

John

 

[Sevens]

In my close circle of GunDoods, we have four 845's. The one that one of my bud's has absolutely does the hammer bounce on any/every unimpeded dry fire. When he first took delivery of it, he was worried and I suggested that he take a deep breath, do the pencil test as described by JohnHL above and report back.

That pistol bounces every time on a dry fire with nothing in the chamber to change the result. It also passes the pencil test 100% of the time and has never had a misfire on the range either.

Obviously, a Performance Center 845 Limited and an old school 469 are not much more than distant kin. The parts inside are fitted differently but the design is much more than "similar."

 

[Borderboss]

I spent a half hour yesterday dry firing with the pencil and the hammer didn't stop at half cock a single time. I think my next step is to take the gun to the range and run a couple of hundred rounds through it, and then judge the results.

 

[Sevens]

Range trip and many hundreds of rounds through this pistol in on the menu, but you passed the first test with a big thumbs up.

I'd continue the pencil test if you have any free time in front of the TV.

 

[bigggbbruce]

And for a SD gun.. it's DA so just pull the trigger again...

 

[JohnHL]

I spent a half hour yesterday dry firing with the pencil and the hammer didn't stop at half cock a single time. I think my next step is to take the gun to the range and run a couple of hundred rounds through it, and then judge the results.

A pencil (or a primer) will typically absorb some of the shock contributing to hammer bounce and the hammer then doesn't bounce back to half-cock.

IF the hammer were stopping at half-cock before reaching the firing pin, I would think it most likely would have manifested itself during your testing.

John

 

[Borderboss]

A pencil (or a primer) will typically absorb some of the shock contributing to hammer bounce and the hammer then doesn't bounce back to half-cock.

IF the hammer were stopping at half-cock before reaching the firing pin, I would think it most likely would have manifested itself during your testing.

John

That's what I'm hoping. I figure the range session would show that.