6904 Question

[Jaxinc]

I went to the range today and fired off a few hundred rounds from my 9mm, aaand had two occurences where the slide went into battery, hammer back, after the magazine was empty.

Checked the pistol each time, saw nothing jammed or lodged in the chamber, barrel or slide, and not sure why it did that. It shouldn't have cocked after emptying, the slide should have locked after firing the last round.

I keep the gun very clean, clean and oil after every trip to range or 200rds.

The pistol never jammed, had no extraction problems, but the slide went forward and the hammer back after emptying on two occasions. Is this normal on rare occasions or would there be a cause for this?

Edit: Just thoroughly cleaned and oiled it, still saw nothing to cause it while cleaning.

 

[handgunner356]

Sounds like a weak mag spring or worn follower not lifting the slide stop.

 

[dbarale]

And, while it's not "normal", it is fairly common for all semi-autos to have a slide lock hiccup at times. Label your mags and note which one is being used when it happens. As mentioned above it is most likely a worn spring or follower.

 

[Jaxinc]

Was thinking that about the mags too, noticed it did it on two particular mags, oddly though the mag it did do that on has a particularly strong spring in it. I have the OE 12rd blued and 4 OE 12rd steels, and it did it on the steels.

Not sure on the follower.

And, while it's not "normal", it is fairly common for all semi-autos to have a slide lock hiccup at times.

Will keep that in mind.

Don't go to the range for another month, having to spend 3k on car repairs... don't exactly have money to blow on a few hundred rounds every month.

 

[ispcapt]

Watch where you place your thumbs. High thumbs is a common result for slide not locking. You won't realize you're doing it. Happens during recoil and it doesn't take much of a bump. It doesn't take the same pressure as when the slide is locked back and your release the slide lock. During recoil the thumb will hold it down just long enough that the slide notch doesn't catch.
Also will sometimes see a premature slide lock back if guys put their thumbs just under the slide lock. During recoil their thumbs will hold the slide lock up.
Could also be as the others described as a mag problem. First I would do tho is relocate your thumbs where they're completely clear and below the slide lock.

 

[Jaxinc]

I do keep my fingers/thumbs clear of the slide, so definitely not that.

Fingers wrapped around grip, thumb resting over mag release, second hand wrapped over other fingers and second thumb on top of first. Neither of which is near the slide.

Thinking it miiiight be the follower, honestly wont know for sure until I put another couple hundred rounds through it. The pistol seems to be getting more accurate the more I shoot it, I don't think the previous owner ever broke it in... I mean for a 20yo or so gun, it was VERY clean and hardly any wear on the slide or rails. So this might just be part of it breaking in, dunno.

 

[tpd223]

First, it is normal and the way it should be for the hammer to be back when the gun is empty, but the slide should lock back as well.

Two things cause this in my experience (at least the two most common), your thumbs are in the way of the slide lock (most common), or the mag spring is weak/follower is worn/or both.

Are you a right handed shooter? If so, shoot it left handed and see if the slide locks to the rear, if so, it's your grip.

Mag springs and new followers are cheap parts to replace.

 

[Jaxinc]

Far as that is concerned I can replace the entire mag, believe the springs for the 69 series from wolf are 20 a piece. Though the springs are really stiff, but I will compare the mags later and see if it isnt the follower. Can't really pull my mags or pistol out at work and check >_>

I am right handed, but the way the grip is in relevance to my hand makes it hard for me to engage the slide lock, but I can try firing left handed and see if it changes anything.

Ill take a picture later of how I normally hold it for reference, I know everyone is different and such.

 

[handgunner356]

$20 from Wolff should get you a three pack of mag springs, they run about $7 each. You might want to check with S&W, Brownells or Midway who also stock S&W parts to get both floowers and springs together and save on shipping charges. A light load/too strong of a recoil spring/loose grip or combination of any those can cause the slide to not fully cycle to the rear enough to catch the stop. You can get a idea of the mag springs by inserting the empty mags and holding the slide back and feel how much tension is pushing the slide stop up.

 

[Jaxinc]

Thanks for that^

Going to do that will all five of my mags and see if I see any difference.

 

[Jaxinc]

It is the follower on two of the mags.

The OE blued and 2 of the OE steels the follower is cut longer than the other 2 steels. It's not much shorter, and the slide still locks when I pull it back, but I can see it causing a hiccup after firing off a few dozen rounds.
Since the mags are virtually identical, minus that, not sure how they are cut different since they're all OE.

 

[holyokeman]

I am having the same problem with my 6906. It has been back to S&W twice with no solution. Took it out last week and after the 1st mag of 5 rounds went flawlessly, the same problem occurred with mag #2, plus a shell failed to eject, thus causing a jam. I have replaced the mag springs & followers with wolf parts as well as wolf recoil springs to no avail. I am filling out an exact report of what transpired including the 6 brands of ammo I tried. I am NOT HAPPY as this is return # 3. I hope what they say about the 3rd time being a charm is true and they get it right this time.

 

[raw6464]

If you've replaced the mag spring it IS the recoil spring. I know from experience.