Follow-up on sending my Shield back to S&W..

[Dave270]

On Feb. 24th., I posted that I had to send my Shield 9mm back to S&W for what Customer Service said was a "dead trigger".

On Monday, I received a phone call and an e-mail from S&W saying that my Shield was repaired and was sent out Monday. S&W said that they had replaced the trigger bar, checked everything else and had test fired my Shield.. Then the technican asked me if I had ever taken the Shield apart by locking the slide back, moving the take-down lever to the down position and then, instead of moving the sear deactivation lever down, and just pulled the trigger and removed the slide.. I told him that I had done that once or twice, because I read about it on this forum, and he said that doing that and not following the manual is probably what damaged my trigger bar. He said that they had received several Shields with the same problem as mine, and that in each case, the Shield had been disassembled using the trigger instead of the sear deactivation lever.. He said that sooner or later, using the trigger method would cause trigger bar problems.

I know a lot of you on this forum have said that was the way you disassembled your Shields, so I thought that a heads-up was in order.. But from now on I am going to follow the manual and use the sear deactivation lever whenever I disassemble my Shield..

This is not a criticism of anyone or the method you use, just what S&W told me...

Dave

 

[chaseman31]

I do it that way everytime, but not anymore, will do it the way the manual states from now on. Thanks for the heads up....

 

[OKFC05]

He said that sooner or later, using the trigger method would cause trigger bar problems.

Thank you for posting this information again.
I posted it a couple of years ago, and was promptly assured S&W did not say it and I was an idiot.
I hope you have better luck.

 

[Prasko]

Gonna need clarification on this.

Exactly how does it damage the trigger bar?

I have a pretty good understanding of how this pistol works, and I can't for the life of me figure how pulling the trigger to take it apart is any different then pulling the trigger to fire the gun.

 

[craign]

I went to Smith and Wesson's website and the M & P Shield page. There is a YouTube link that shows pulling the trigger for disassembly.
This is the link from Smith and Wesson: [ame]https://www.youtube.com/watch?v=_xVUJAxv3SM&feature=youtu.be[/ame]

 

[Dave270]

Fellows....

I am not here to get in an argument, nor am I a S&W Armorer, so I don't know all the technical answers. I just posted what S&W told me. You can do whatever YOU want to do..

Dave

 

[Randyp1234]

I went to Smith and Wesson's website and the M & P Shield page. There is a YouTube link that shows pulling the trigger for disassembly.
This is the link from Smith and Wesson: https://www.youtube.com/watch?v=_xVUJAxv3SM&feature=youtu.be

It says right on the screen shot that this is a Nutnfancy video.

 

[feelinlucky]

On many, if not most, DAO partial or fully cocking striker fired semiautomatic handguns, one has to pull the trigger to facilitate disassembling the weapon... which has led to some unintended discharges because someone failed to assure that the chamber was empty before trying to disassemble the weapon... which has cause numerous gun makers a lot of legal headaches.

S&W included a sear deactivation lever, and they encourage its use, to facilitate disassembly of the firearm without pulling the trigger... therefore avoiding the above mentioned potential legal headaches.

I have never used the sear deactivation lever... and I have never had any problems with any S&W M&P's. I have three of them... and I disassemble and clean them regularly.

Go figure.

 

[Triggerman66]

I like the idea of the take down lever as it is a sure way of insuring the chamber is empty. To me it is easy to flip the leaver down with a finger. Seems like the military likes this feature in that they request a similar system in any new handgun to be considered for adoption.

 

[craign]

It says right on the screen shot that this is a Nutnfancy video.

Yes, I know. Apparently I was not clear, the link is on Smith and Wesson's website as if they endorse it. Why in the world would any company put a link to anything that shows incorrect information, especially something that might damage a product?

I would never have known how to disassemble the Shield by pulling the trigger if I had not visited the Smith and Wesson Shield page.

 

[Targets Guy]

I pushed the sear deactivation lever down the first day I had the pistol and have never seen it again.

 

[CB3]

The trigger bar has a small, adjustable tab that engages the sear. Bending this tab makes for earlier or later sear engagement.

Too early engagement could mean the striker block safety has not yet been pushed out of the way by the other tab on the trigger bar, so the gun won't fire even though the sear has been pushed up to release the striker.

Too late an enagement produces less movement of the sear than necessary to release the striker = dead trigger.

Adjusting the trigger bar/sear engagement likely would have fixed Dave's dead trigger. However, with the gun in hand, it was easy for a S&W 'smith to replace the trigger bar (and maybe other parts) with upgraded parts, adjust them and send the pistol back. The original trigger bar may not have been ruined, but the adjustment tab may have gotten compressed.

How?

TDL = Take Down Lever
SDL = Sear Deactivation Lever

CB3 theory (not a gunsmith):

Dry firing does not hurt this gun with the TDL up. The barrel is locked in the slide, and the barrel lug engages with the UP TDL. This prevents the slide from going forward off the frame.

When the slide is locked to the rear and released, the recoil springs propel it forward, the barrel rises to lock into the slide and the barrel lug makes contact with the TDL to prevent further forward travel of the slide and barrel. This is being in battery.

Meanwhile, the striker tab has engaged the sear. The striker is cocked, putting striker spring pressure on the small engagement surface between the sear and striker tab. There is a balance of forces here with the barrel being in battery and the striker cocked. Only the striker spring force is being exerted on the sear.

If the TDL is down, the barrel lug no longer engages that major locking surface in the frame. The slide would come off the frame EXCEPT for the sear being engaged with the striker. So, with the TDL down in the disengaged position, the only mechanical device preventing that slide from traveling further forward is the small surface of the sear. I doubt it is actually designed to be used like the TDL. The recoil spring pressure, instead of bearing on the barrel lug and TDL, is now added to the striker spring pressure on the sear.

Thus, if you allow your slide to slam forward with TDL down, you may be accelerating wear on your sear/striker interface and the sear axis. I doubt this force could be transferred to the trigger bar, but if so, it would compress the trigger bar sear tab and change the firing timing. Easing the slide forward would be a better method than allowing it to freely slam forward when the TDL is rotated down.

Thus, it works to dry fire your pistol with the TDL down as a means to release the slide off the frame, but it probably puts increased wear on parts that could effect the timing of your trigger system.

I think I will go back to using the SDL when removing the slide.

Thanks, Dave

(BTW, my original post before thinking this through was going to be how ridiculous it is to think dry firing could hurt this pistol. )

 

[Hunter8282]

I wish the Shield had a built in tool like the Full Size does. If I am home at my cleaning bench its fine, but otherwise I have a hard time getting the lever with just my finger.

I wonder how many times of "doing it wrong" it takes before significant wear or damage occurs?

 

[Stetto]

Wow, I really appreciate this being brought up; The first time I broke my Shield down I couldn't find the SDL. The little black & white photo in the destruction manual just wasn't displaying it clearly enough, or I wasn't paying close enough attention to detail, but I actually pulled the trigger by accident and the slide came off...It was during reassembly that I found the sear lever. I believe, being as I'm new to S-A handguns, and the lever was created for a reason, I'll just develop the habit of dropping that lever every time...Thanks for posting, Dave!

 

[Dave270]

I wish the Shield had a built in tool like the Full Size does. If I am home at my cleaning bench its fine, but otherwise I have a hard time getting the lever with just my finger.

I wonder how many times of "doing it wrong" it takes before significant wear or damage occurs?

It only takes ONE time and then when you pull your weapon out to use in a "situation" and you pull the trigger and nothing happens, that is what I call an "OH-****".

Dave

 

[Prasko]

Thus, if you allow your slide to slam forward with TDL down, you may be accelerating wear on your sear/striker interface and the sear axis.

If you do this, period, you deserve a broken gun.

It's common knowledge you down let the slide slam home on an empty chamber.

With modern pistols you may be able to, but even then, I was always taught not to.

 

[CB3]

If you do this, period, you deserve a broken gun.

It's common knowledge you down let the slide slam home on an emptying chamber.

With modern pistols you may be able to, but even then, I was always taught not to.

This has nothing to do with whether the chamber is empty. What accelerates wear (possibly) is letting the slide slam forward when the TDL is down out of the way of the barrel lug.

Letting a slide slam forward on an empty chamber when the TDL is properly engaged (up) does no harm to a pistol. The process is the same whether the pistol is loading a round from a mag or the chamber is empty. The TDL stops the forward motion of the slide regardless of what is or isn't in the chamber.

Having the slide locked open and dropping a round in the chamber then letting the slide slam home requires the extractor to jump over the rim of the chambered round. That can cause extractor problems if done frequently.

 

[shawn mccarver]

When the M&P was first introduced, I wondered if disassembly by pulling the trigger like the Glock would damage the pistol in any way.

The man from S&W responsible for designing the M&P said it would not damage the pistol in any way; it was simply not recommended for safety reasons.

I have used this method all these years, and have never had a problem: Unload. Check three times. After rotating the take down lever down, ease the slide forward to the "in battery" position, then pull the trigger when the slide is stopped in the "in battery" position, then continue by moving the slide forward off the frame.

So, now S&W is saying this will damage the pistol?

If that is true, then this is another weak point in the design that makes it a non-starter for serious LE or military use. Sorry, S&W.

That said, follow S&W's instructions.