Hello, looking for some insight on my 4006.

I recently bought it and love everything about it except....the single action trigger pull.

My 5906 has a very crisp let off and pull in single action.

The 4006 stacks kinda bad, about 2 to 3 "stages" that you can feel before it finally is back far enough to release the hammer. These noticble "stages" are very close together. It's hard to describe. It's like there is something pressing against the draw bar casuing it to hang up ever so slightly for 2 to 3 times as you pull back in single action. It doesn't take anything to overcome it but it is extremely annoying and making repeat shots unpredictable for me. You can also hear this as you slowly ease the trigger back. Kind of a chattery click.

Does anybody know what could be the cause of this? None of my other thrid gens do this.

Sounds like it could be a bent or damaged Trigger Play Spring, which is the brass thingy riveted on top of the drawbar. If that's the case, S&W can repair the problem by installing a new one for you, you'll just have to contact them about it.

I agree on the spring.

Thank you to both of you for the replies. I compared the play spring to.the one in my 5906 (which has a butter smooth single and double action pull) and it appears to be functioning correctly. It holds light pressure against the trigger in single action mode as it should.

I ended up stripping the frame and started checking some things and giving it a good cleaning. Nothing appeared oit of the ordinary.

What I am noticing is that the problem only occurs when the slide is on the frame.

I put the slide on as far back as it goes without putting any tension on it. I left the takedown pin out. I cocked it into single action. I worked the trigger like I have been to just before it releases the hammer. Same gritty pull and stacks about three times in a tiny distance.

Now, I could see the front of the drawbar and the drawbar plunger spring through the takedown hole. As I work the trigger back slow, I can see the the drawbar "jumping" and almost what looks like binding each time it stacks. Could there be something in the plunger spring hole that is causing it to hang up like this? Anything in the rear portion of the frame? When the slide is off and I work the trigger it's as smooth as can be. What contacts the trigger when the slide is put on? It looks to me like the feed ramp gets awfully close to the trigger when assembled......


Please offer any insight you can. I have 5 3rd gen pistols and all are like butter except this one. The gun is a beauty but the trigger is killing it for me.

Sorry, any further help would have to come from someone with a better understanding of the mechanics of these pistols then myself. I can basically change the oil and tell you if you have a problem with the alternator.

You might consider adding the word 'Problem' or 'Issue' to the end of this thread title, it could help to draw the attention of some of the very helpful and knowledgeable people who frequent this forum. Just a thought.

When Fastbolt weighs in your problem will disappear.

Randy

Thank you, thats a good point. I just changed the title now. I really don't want to send this pistol into smith.....I wish I could just figure it out. Last time it was my 5906 and it ended up just being a finicky recoil spring and they wanted to trash the pistol and offer me a new plastic gun. Don't get me wrong, I have various plastic guns but I specifically buy 3rd Gen smith's because they are all metal and stainless to boot. Only other good all steel options these days are cz's..... and 2011's which I couldn't care less for.

I couldn't tell you how nice that would be if that was the case. It's driving me nuts how nice and clean this gun is with a trigger like a Smith 642 fresh out of the box.

When the frame is fully assembled, but the slide off the frame, and the hammer is cocked in single action ... does pulling the trigger result in the front (head) of the drawbar "jumping"? Is that what I'm reading?

Does your 59XX do the same thing, with the frame fully assembled but with the slide/barrel off the frame? I'm guessing not, or not to the same degree?

It's not uncommon for the drawbar head to "jump" if the drawbar plunger wasn't properly captured in the circular notch at the front of the drawbar head.

Checking the drawbar plunger and its spring isn't a bad idea during an armorer level disassembly & inspection. The plunger & spring seldom wear out, but improper assembly (if the spring has been removed from the plunger at some point) can sometimes cause problems. The small end of the spring is installed on the plunger, resting against the back of the plunger. Tough to get off and on, and doing so will usually scratch the aluminum plunger.

In older 3rd gen guns, the plungers lacked the tapered "bullet point" front tips, and had squared front ends. This revised tapered front tip was added to help eliminate any potential for the square front tip to catch against the inside edge of the plunger springs during compression. (Think a little series of potential bumps as the spring was compressed over the front of the plunger.)

Also, the later production 3rd gen frames had a hole machined into the front of the drawbar plunger spring well. This was done to help reduce the potential for hydraulic lock to occur if the spring well became fouled & gooey with migrated lube, and increased pressure might result during the plunger being pushed into the spring well. The hole at the front let pressure bleed out of the spring well (channel). (No, DON'T get out your drill motor to use on older 3rd gen's!!!)

I'd check to make sure the plunger spring wasn't broken ... and the spring well was clean and DRY ... (and don't leave any Q-tip debris or cotton tip heads inside the well!!) ... and then make sure the rear "ball" of the plunger was properly captured in the drawbar head's notch (it can easily slip out while an armorer is distracted trying to hold the drawbar forward and installing the trigger pin).

While it's probably more common for a cracked drawbar to be noticeable in DA mode (stretching apart during the DA trigger stroke, as more pressure is applied), it's always a good idea to check the integrity of the drawbar. In the older drawbars a stress riser could sometimes result in a crack located at either rear corner (sharp corners in older drawbars), or in the middle of the drawbar tail, behind the disconnector tail tab (thinner machining at that spot in older drawbars). Just grasping each side of the drawbar, toward the rear, and pulling outward can usually reveal any cracks.

If it's a cracked drawbar, it's best to let someone familiar with 3rd gen's "drop in" a new drawbar. Drawbars have to be checked for proper engagement with existing parts, checking for normal fit & function (no Skips-DA, doesn't rock off in short DA pulls, holds in SA, etc). Sometimes other new parts may have to be installed so they all properly work together.

Also, every now and again even a new drawbar may produce a Skips-DA condition, and have to have the drawbar head's radius CAREFULLY filed with a 5 /32" chainsaw file in order to put it within normal spec with the trigger pin, and the drawbar's tail properly reach and engage with the hammer's pick-up and throw notches. It doesn't happen all the often, and it's not something even practiced in the armorer class ... although it is mentioned and discussed in the manual and the class ... but it needs to be recognized and addressed when it does happen.

Naturally, checking for any damage or out-of-spec conditions on the rest of the working parts & assemblies would be needed to make sure nothing else is occurring. Can't do that via the internet. There are a couple of spots in guns with the older flash-chromed parts that can easily have some machining burrs which can sometimes be felt as roughness during a slow and careful SA trigger pull while sitting at the bench, but they aren't something to be addressed at the "hobbyist" level. Too easy for a file or stone to cause unwanted (and unrecognized) damage when being used by untrained & inexperienced hands.

One other simple thing to check is the freedom or movement of the trigger pin in the frame. When the frame is assembled, and the trigger is pulled, the ends of the trigger pin ought to freely move back and forth, with the trigger's movement. If not, sometimes a bit of roughness may have to be dressed on the trigger pin (removing it from the frame and rolling it lightly in some fine crocus cloth can usually remove any burrs which might be present, but not easily seen). If that doesn't work, then replacing the trigger pin, checking the frame holes for damage (remember the frame is the EXPENSIVE, registered part of the firearm, so don't start "fixing"!!), as well as checking to make sure the trigger assembly isn't damaged or out of spec may be necessary.

Just some thoughts. An examination by an armorer or gunsmith familiar with 3rd gen TDA pistols is a better bet.

__________________
Ret LE Firearms inst & armorer

I really appreciate your reply and talk about in depth! I'll tell you what, I'm going to make a video and post it privately to youtube. Can I post a link to it here? And to clarify, it does this when the gun is fully assembled. I can do it when the slide is off the frame and work the trigger and the chattering is not present. So it is a problem when the gun is fully assembled only. I'll post a video shortly.

So ...

The drawbar head doesn't jump when the trigger is pulled (slide off to enable seeing it) in SA mode?

The drawbar plunger and spring are in good condition?

The drawbar isn't cracked?

The trigger pin freely rotates when the trigger is pulled and released?

Okay, IF this crunchy-whatever is happening when the slide/barrel are installed and the gun is fully assembled ... and it happens during the trigger pull ...

I'd still check the drawbar, particularly on the R/R corner, where the firing pin safety exerts pressure against the front of the drawbar tail as the lever is being pushed upward ... and ...

I'd inspect the freedom of movement of the firing pin safety plunger (steel plunger, on right side of slide). If the firing pin safety plunger spring has been clipped, bent, folded over or otherwise damaged when the rear sight base was installed (originally or later on), the plunger may not be moving like designed.

Video clips are often much less helpful than you might think. They don't let you handle and FEEL what's happening, nor do they usually offer the angle or perspective that's desired. Obviously, they're not a substitute for being able to handle, disassemble and inspect anything.

Sometimes, as was already mentioned by someone else, I thought, little weird "problems" can be the result of unrecognized assembly abnormalities. You'd be amazed at how easily a sear tail can be located on the wrong side of the sear spring, for example.

Sounds like this pistol ought to be carefully checked out by an armorer or gunsmith familiar with S&W TDA pistols.

If you lived near me I'd be happy to inspect it as a courtesy. Sorry.

__________________
Ret LE Firearms inst & armorer

Ok, see if this helps. The sound seems to be coming from the rear of the slide. I suppose though it could just be traveling to through the trigger system somewhere....

It shouldn't be making that noise when the hammer is cocked and the gun is disconnected because there isn't a magazine in it. (Presuming proper assembly of frame components.)

If I had the gun in front of me, I'd suspect an assembly problem, and strip it down to check for anything improperly positioned when assembled, or damaged.

Now, if someone has fooled around with the magazine safety (removing it), or otherwise modified something? I'd really check for damage.

So, does the drawbar head jump during the trigger pull, or not??

__________________
Ret LE Firearms inst & armorer

Yes it does, sorry. In my second post I mentioned I did notice the drawbar almost looked like it was binding and releasing as I pulled the trigger fully back. I had the gun all the way apart and nothing seemed bent or broken. I didn't inspect the drawbar too closely though. The mag saftey lever appeared to be in good condition. I don't understand why people have such a problem with the mag saftey. How many times would you fire a semi auto without a magazine? I really hope somebody didn't mess with that. Double action feels fine all the way back though. It's just the single action pull.

I'll break it down and check everything again. I know the drawbar plunger spring was seated properly but maybe the spring is binding like you said before. The trigger pin is moving freely so it's not that. The link is when the slide is on the frame. What contacts the slide in single action mode?

Sorry, but just to clarify....in the video, the magazine is removed from the assembled gun and after cocking single action, you are pulling back the trigger, is that correct?

Can you try removing the grips and running the same test to see if the problem persists with the grips removed? (You will be able to observe the rear of the drawbar and components)

I have seen "ridges" or machine marks inside the hole for the drawbar spring and plunger....check if you can with a magnifier, or probe the hole to check that there are not any gross imperfections that the spring would catch on.

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

If the drawbar head isn't tensioned by a properly positioned plunger, the tail isn't tensioned and positioned properly during operation.

If the disconnector isn't tensioned and positioned properly, the drawbar tail can't work as intended.

Is the sear tail located to the front of the sear spring?

Gotta run. 2-day road trip to finish.

__________________
Ret LE Firearms inst & armorer

Thank you I'm going to check for that in the plunger hole. I'm really starting to believe this is where the problem is. There was no discernible hang ups or problem areas on the drawbar when I checked inside the frame and on the drawbar when I had the frame taken down. I will it without the grips and see what I can see. Yes I have the magazine out because that way I can continually pulling the trigger without having to re-cock for the demonstration but even with the magazine in and allowing the hammer to fall the trigger feels the same. I will report back tonight thank you.

ok I checked the things you mentioned and everything checks out. I'm relying on the issue being the drawbar spring/plunger now. Im going to carefully clean hole out with some 1000 grit sandpaper and a small rod. maybe the plunger is bent too. I'll report back what changes if anything. Thank you for taking the time to reply to me.

Thank you to all who replied in helping me to diagnose this horribly annoying problem.

As per suggestion, I left the grips off as I worked the trigger like I have been. This allowed me to trace the noise and feel of this binding.



And the winner is........the farthest lever to the right as you are looking at the back of the pistol as if you were shooting it....the silver plunger (firing pin saftey button I believe?) in the slide was for some reason scraping up against it's channel in the slide and was making this nasty trigger problem. I took a plastic toothpick and pushed it all the way down gently into the slide and allowed it to come back up and presto! The problem is gone. I'm sure it will come back when that plunger in the slide manages to get itself into that position again. Any thoughts as to what could be causing it to do that? A spring or burs in the channel perhaps?

I really appreciate all the suggestions and in depth help with this. Trigger feels like butter just like my 5906 now!

The spring may have been misaligned, or it may be damaged. If the rear sight has been removed, the spring could have been compromised if the sight was not re-installed properly. Oxidation can also be a problem.

Make sure the firing pin safety lever is not damaged (bent/altered) and the safety plunger is undamaged, and is working as it should. This is a critical safety mechanism.

The safety plunger should move up and down freely, with only slight resistance from the spring. The lever should be free of damage or excessive wear. Check also that the firing pin is being blocked when the plunger is "down".... and is free to move when the plunger is "up", or depressed fully.

If you recently purchased the gun, I would seriously consider having it examined and function checked by a S&W pistol armorer....or a local qualified gunsmith, familiar with these 3rd generation pistols. This would be particularly important if you are planning on carrying the gun at any point.

There should be no compromise when it comes to safety.

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

Thank you for the help. I did the checks of the lever and the plunger and it seems to be in like new condition and functioning as it should now. However, you are correct. While I'm glad that the problem is resolved for the most part, I feel that it needs to be checked out by a pro. I bought it about 3 weeks ago and I may carry it as a open carry piece here and there. I just need to locate a smith that knows these pistols.....Thank you again!

Have it inspected. A smith familiar with 3rd gen TDA's can check the condition of the FP safety plunger & spring. Not rare for the spring to have been damaged during a rear sight base removal/installation if someone was either unfamiliar or inattentive during installation. The top of the spring can get caught and damaged by the left side of the sight base during sight installation.

The plunger, plunger channel and FP also need to be inspected. Could be a burr broke loose inside the channel (loose and caught up within spring coils at times).

If the plunger hasn't been freely moving, the FP and the FP safety plunger need to be checked for peening/chatter that may have been caused by improper clearance between the FP & FP safety plunger (if the plunger's been "sticky"). Also, the FP channel should be checked for any debris/loose burrs, since the FP safety channel connects to the FP channel.

Care needs to be taken when the rear sight base is removed/installed, as the parts (and whole assembly) are getting sort of rare.

__________________
Ret LE Firearms inst & armorer