6906 Issue......RESOLVED!!!

[pumpedTSI]

I just received a 6906 LE trade in from CDNN and was very pleased with the condition.....not beat up at all and seems to have not been fired much. Anyways, she was quite filthy and had not been cleaned after previous firing so I pulled the grip, field stripped and gave it a nice cleaning and light lube. I took it to the range and accuracy was very acceptable however then the issues started......after every mag is empty the slide does not lock open. Its a LE stainless mag that came with the gun....is this a mag issue? Next problem, on the second mag the slide failed to cycle completely, it stripped the round from the mag, loaded it into the breech but did not lock forward completely and seemed to "jam" or "stick".....I dropped the mag, pulled the slide back and ejected the round which "looked" ok. I reloaded and started again and after 5-6 rounds it happened again, slide "stuck" in the half load position....what is causing this? Mag issue related to the last round non lock open or is this two problems? Maybe a weak recoil spring? Anybody have any ideas? TIA....

PROBLEM SOLVED!!! Got the pistol back from S&W yesterday......took about 3 weeks as they indicated. Apparently the "adjusted" the extractor to factory spec and "adjusted" the slide stop to spec and test fired....total cost = $zero. Anyways, took her to the range tonight and ran 100rds thru her with zero malfunctions......all good. Gotta love S&W service.....

 

[oliveview]

Having blasted thousands of rounds through my 6906 over the years, and NEVER having literally any issues whatsoever, I have to wonder if the mags might be the first place to look. I'm not familiar with whatever LE mags those might be, but my factory stainless 12-cap ones have been flawless. On top of that, I've never changed a single spring in the gun or the mags, and again, never have feeding or ejection issues.

So, check the mags, first, then look to the recoil spring if need be.

 

[lawman90]

It does sound like it could be a mag issue. I would replace the magazine spring. With any used, especially police trade-in gun, I always replace the recoil spring and magazine spring(s) by default no matter how clean or new the gun may look.

 

[Jeb21]

I agree get new mag spring from wolf as well as a recoil spring.

 

[yeti]

I agree get new mag spring from wolf as well as a recoil spring.

Sounds like sage advice to me.

 

[ColColt]

Worn follower not allowing the lobe of the slide stop to trip into lock back...another possibility.

 

[pumpedTSI]

Colt, I doubt the worn follower since the gun shows hardly any wear.....I may try another few rounds thru it to see if it reoccurs and if it does I'll swap in one of my 669 or 5906 mags to see what happens....if its the mag I'll just change out both springs as suggested...wheres the best place to get the Wolff springs?

 

[ColColt]

From Wolff springs.

Springs for SMITH & WESSON NUMBERED SERIES Semi-Auto Pistols

For Use in:
469, 669, 6904, 6906, 6924, 6926, 6944, 6946, 9mm
411,4003,4004, 4006,4026,4043,4044,4046, .40 S&W

 

[Fastbolt]

As has already been mentioned, the first thing I'd do is replace the recoil and mag springs. Factory springs are fine. (For a while I used Wolff +5% mag springs in a couple of issued 6906's I carried, with factory recoil springs.)

The factory recommendation to armorers for recoil & mag spring replacement used to be based on free length of the springs compared to new ones, but then the company simplified their recommendation by telling armorers to replace recoil & mag springs either every 5 years of use (pretty much meaning mags left fully loaded in LE guns), or every 5,000 rounds fired, whichever came first.

I've seen mags dropped onto hard surfaces (concrete) by cops now and again, and it's not impossible that a "used" mag might have an issue with the lips. New magazines are costly, but a good investment.

Followers can eventually develop a deformation where the lip of the last round digs into the follower under recoil. If that spot gets too rough it might interfere with feeding of the last round, but I've seen them take a lot of abuse and keep feeding normally. I've been reminded by the factory that the black followers used in the 6906 are slightly different than the black ones used in the older 59XX mags (due to the increased slide velocity in the shorter 669/6906 guns and how it can affect feeding). I never could see the subtle differences by eye, but I believed them and kept them separate from those used in the older 59XX mags.

 

[BillXL]

ColColt and Fastbolt are right about checking the mag follower. A friend of mine and me both bought 6906s that were ex CDC guns and we got 2 mags with each one. They all had some wear, but one had a rough worn follower and it consistently did not lock his slide back on the last round. That mag in my gun worked ok most of the time. If you look closely you will see that a groove has been worn where the lever on the slide lock hits the follower. Hope that helps. BTW I bought mine in the fall and have really enjoyed the gun. They are a nice weight and size.

 

[pumpedTSI]

Nope.......its not the mags or the recoil springs.....I switched mags with my 669 and 5906 and the slide was still was not locking fully forward after firing....I also switched the guide rod and spring from my 669 with same results....after firing it will move the slide forward about 85% and then "sticks/jams"...with a slight push on the rear of the slide it will lock into position but I feel a slight resistance like a burr or something but I've checked slide,barrel and frame and see nothing...maybe a trip back to S&W is in order?

 

[youseemym&p]

you could try a +10% recoil spring. give it some more umph

 

[ColColt]

....after firing it will move the slide forward about 85% and then "sticks/jams"...with a slight push on the rear of the slide it will lock into position but I feel a slight resistance like a burr or something but I've checked slide,barrel and frame and see nothing...maybe a trip back to S&W is in order?

If the round enters the chamber ahead of the extractor and fails to go to battery that's a mag problem, pure and simple especially if the slide lacks about 1/4" going into battery. That slight resistance could be the extractor claw trying to cam over the rim as your pushing the slide forward.

 

[Silversmok3]

An extractor problem may be the culprit. Out of the five S&W used semi-autos ive purchased only one-a 5906-had a problem, and it was the extractor. Upon acceptance my 5906 had two compound failures every magazine. Looked something like this:

After a new recoil spring, the gun would malfunction at random. Bought a new factory magazine , and with the changed parts the weapon went 90 rounds...and did this from rounds 93, 96, and 99 out of 100:

Id send it in to the factory with a picture & written description of the problem. The price to repair it will run something close to $100 give or take.

 

[pumpedTSI]

Colt,
I've switched mags and its still doing it with my 5906 and 669 mags ALTHOUGH it wont lock slide back on the factory mag it came with but WILL lock back with my 669 and 5906 mags....there is a slight groove worn into the follower on the factory mag.....

 

[ColColt]

Look at the little lobe on the slide stop that penetrates the frame. That's what triggers the slide to lock back when the follower rises up to activate it. See if anything looks odd or out of the ordinary about it...a burr on the edge for instance being too long could do it but I wouldn't' think that's likely as the problems seems sporadic. I'm certainly no gunsmith but I feel your pain as I've experience my fair share of pistol problems...fortunately not very many of the 3rd Gen models but others.

After a new recoil spring, the gun would malfunction at random. Bought a new factory magazine , and with the changed parts the weapon went 90 rounds...and did this from rounds 93, 96, and 99 out of 100:

Silver, did the extractor/spring replacement fix your problem? Which was it?

 

[pumpedTSI]

Colt,
I know what you mean.....it bugs the absolute **** out of me owning a gun I cant trust my life on if the need arises....

 

[W.E.G.]

was quite filthy and had not been cleaned after previous firing... field stripped and gave it a nice cleaning

Are you sure you cleaned out the channels and slots for all the dingus-levers?

 

[rebelray84]

I got one of those and had to literally drown mine in break free to get it in working order.Evidently these came from some desert area because there was sand in every crack and crevice.It is now 100% after it's breakfree bath,200 rounds down range without a hiccup using the LE mag it came with.

 

[Fastbolt]

The gun needs to be checked by a gunsmith familiar with S&W pistols, a S&W armorer or the factory. You may have a couple of things going on at the same time. That can make diagnosis a bit tricky, and requires someone knowledgeable in the guns to examine it in person and identify the problem(s) that may exist.

Some thoughts on what has been posted so far in this thread ...

The failure-to-lock back on an empty mag ...

If the other mags are letting the slide lock back when they run empty, but the one that came with the gun isn't, it's possible the mag spring and/or follower that came with the used 'factory' mag need to be replaced. (Not a bad idea anytime a used mag is involved, anyway).

The erratic and inconsistent feeding ...

Failures-to-feed are typically caused by the ammunition; the magazine(s); a dirty chamber; a damaged extractor; a barrel with an overly long tab (rear of hood); or a recoil spring.

Are the frame rails in good condition, or did someone run the gun too long without sufficient lubrication?

While a failure-to-extract can be caused by a damaged extractor and/or a damaged or weakened extractor spring, a failure-to-feed may be caused by a problem at the "other end" of the extractor.

For example, maybe there's excessive gunk, fouling or even some bit of debris that's accumulated under the extractor tail, or within the spring, preventing the tail from pivoting inward and letting the hook move outward as intended during feeding. This can create problems with feeding "timing".

Former LE gun, right? No way to know how it was maintained or repaired (if necessary). If the extractor required replacement at some point, was the extractor fitted correctly? If it was over-filed and is too tight, you can get feeding failures. Was the correct extractor spring used if it was replaced? Too heavy and you can get feeding failures (because the extractor has too much tension). These issues can become complicated by unexpected ammunition tolerances might vary when it comes to case diameter or rim thickness.

Was the barrel replaced at some point? If so, was the tab checked for fit? Too long?

Are the frame camming surfaces in good condition? (Those are the angled surfaces in the frame, to each side of the barrel's feedramp, where the barrel lugs run up & down during cycling.) Are the top points of the those angled surfaces in the frame still within proper spec, so the barrel is release to return up and into battery correctly? It's critical that the top of them are in good condition for proper feeding & functioning. Some peening can normally occur in the 'middle' of the camming surfaces (alloy frames can experience more wear from the steel barrel lugs running up & down them than when a steel frame is involved), but if the top surfaces are damaged the frame is generally not salvageable. (I once had a 6906 alloy frame get pretty peened and worn in the middle of the frame cam surfaces as the round count was approaching over 40K rounds, but the top 'release points' were still good and the gun was running reliably.) This is something I'd leave to the factory to determine, myself.

It can become understandably frustrating to have one or more problems interfering with the normal operation of a gun. Especially one as normally reliable as the 3rd gen guns. However, guesswork can only make things more frustrating, and 'trial & error' attempts by someone not trained with diagnosing and correcting simple problems can make things even more frustrating. Not to mention maybe creating further problems.

Why not call the factory and inquire about having the feeding problem in a former LE trade-in gun be examined and corrected?