New Shield Slide Lock Back Problem

[sweetfoal]

Brand new shield, took home one day only. No live fire other than a few round of dry fire with dummy round.


Only did once to remove the slide following the instruction in the manual, then put it back. After a short while, I've noticed the dummy round has repeatedly having fail to chamber problem. Cleared the gun then found the slide won't lock back. After looked around found the slide is actually not going back far enough, when rack it only goes as far as half inch away from how far it's supposed to go so the slide stop never able to catch.


I rack hard enough made sure that's the end of it. I have been racking this gun for quite a few times since took home, so it's sure not because racking manner. I though it might be the recoil guide rod, but I've been dealing guns for sometime, I put it back carefully and never had this problem with other guns. But this is my first SW pistol, so I can't say I know MP gun well.



What could be the problem? Has anyone seen this before? I searched youtube seems nowhere has mentioned this specifically.

[stansdds]

Welcome to the S&W Forums!

Based on your picture, the slide goes back more than far enough for the slide stop to engage the slide. I presume you have an empty magazine fully seated when trying to make the slide stop engage.

As for chambering a dummy round, is this a Snap-Cap or similar or is this resized brass with no powder, no live primer, and a real bullet seated? If it is a dummy round with a seated bullet, the bullet may have been pressed deeper into the case by repeated loading from the magazine.

Also, I have to ask, what is your level of experience with firearms? If this is the first firearm you have ever owned, I highly recommend going to a firearms safety and training course.

[Saudade]

Originally Posted by stansdds

Based on your picture, the slide goes back more than far enough for the slide stop to engage the slide. I presume you have an empty magazine fully seated when trying to make the slide stop engage. <snip>

It's not far back enough. Note the location of the circle notch by the take down lever.

OP, I've had this happen on reassembly. It's still the recoil assembly. I have to rack mine real hard several times (as if racking a Shield wasn't hard enough), and it will finally seat fully.

[stansdds]

Oh, yeah, I see. About the only thing that would prevent the slide from fully retracting is the recoil spring assembly is not correctly seated.

[sweetfoal]

Originally Posted by stansdds

Welcome to the S&W Forums!

Based on your picture, the slide goes back more than far enough for the slide stop to engage the slide. I presume you have an empty magazine fully seated when trying to make the slide stop engage.

As for chambering a dummy round, is this a Snap-Cap or similar or is this resized brass with no powder, no live primer, and a real bullet seated? If it is a dummy round with a seated bullet, the bullet may have been pressed deeper into the case by repeated loading from the magazine.

Also, I have to ask, what is your level of experience with firearms? If this is the first firearm you have ever owned, I highly recommend going to a firearms safety and training course.

Thanks for response. To answer your questions, the reason I found the slide didn't go back far enough was based on comparing to what's on youtube such as this Smith & Wesson M&P Shield 9mm - Guide and Review - YouTube



By the time this happened, I couldn't recall/register the correct slide position so I have to check on others, see attached picture. It appears in the youtube video the slide is further back than mine.



The dummy round I used are bought from here:

Amazon.com : ST Action Pro - 9mm Yellow Action Trainer Dummy Round - 5 Rounds (Original Version) : Sports & Outdoors

 

Amazon.com : ST Action Pro - 9mm Yellow Action Trainer Dummy Round - 5 Rounds (Original Version) : Sports & Outdoors

I have used mainly glock in the past, experienced fully customized slide, trigger, ejector, firing pin etc, inside out all done by myself, definitely not a novice to guns by any measure. But this is the first MP I have.


I have tried both with and without an empty mag in the Shield, and yes I understand the new Shield tends to be tough to lock back but I was able to (with a mag or manually push the stop up) for at least a day until this happened.

[swsig]

Welcome to the Forum!

Be sure the recoil spring assembly is properly installed, straight and level. The takedown lever must be in the down position for reassembly. In your photo, it is in the up position. The yellow sear deactivation lever inside the magazine well must also be in the down position for reassembly. The 9mm Shield is notoriously difficult to rack, especially when new, so even if you've done everything correctly, it can still be a struggle to lock back the slide.

[sweetfoal]

Sounds like it's the recoil spring. Somewhere on this board somebody claimed the recoil guide rod must be seated perfectly, unlike a glock. I couldn't say I was not careful when seated the guide rod, and I did rack and lock back the slide successfully a few times after resembled the slide before it malfunctioned.


I'm going to have a smith look it. Now I'm paranoid even after it's fixed what would be considered "seated perfectly" to aovid this. As I'm bordering OCD with perfection, still couldn't believe I made mistake with seating the recoil spring, yet it happened.

[sweetfoal]

Originally Posted by swsig

Welcome to the Forum!

Be sure the recoil spring assembly is properly installed, straight and level. The takedown lever must be in the down position for reassembly. In your photo, it is in the up position. The yellow sear deactivation lever inside the magazine well must also be in the down position for reassembly. The 9mm Shield is notoriously difficult to rack, especially when new, so even if you've done everything correctly, it can still be a struggle to lock back the slide.

When this happened, I've already completed the resembling the slide and successfully racked, locked, dry fired a few times. The takedown lever was down when I put on the slide, the yellow sear was down before I was able to remove the slide (this is CA Shield), and resumed when I load a mag in after resembled. All was done by the book. I literally opened the manual on the side with the page open showing these steps. All I did was taking the slide out, removed the barrel, have a look then put everything back.


There must be something I didn't do right, most likely the recoil guide rod was not seated good enough. Or maybe the dummy round somehow interfered it. I did notice it's relative difficult to load the dummy round. For example, I can't drop the round to chamber directly then the slide won't close, not even with a punch on the back. I have to load the dummy round from the magazine.


I also developed a half rack during dry fire, as if checking the round in the chamber with slightly opening the breech face enough to see the round partially pulled out of chamber. Then let the slide bounce back to battery on its own, and reset the trigger. Sometimes it won't go fully in battery but with a punch it usually will.



Maybe Shield is susceptible to malfunction with the way I did.

[Fastbolt]

Originally Posted by sweetfoal

For example, I can't drop the round to chamber directly then the slide won't close, not even with a punch on the back. I have to load the dummy round from the magazine.

Yes, you do load the Dummy round (and live ammunition, at a range) into the chamber from the magazine.

Re-read pages 17-18 of your Shield Safety & Instruction Manual (on loading). Loading the chamber by directly dropping a round into the chamber with the slide open is not how it's recommended.

Originally Posted by sweetfoal

I also developed a half rack during dry fire, as if checking the round in the chamber with slightly opening the breech face enough to see the round partially pulled out of chamber. Then let the slide bounce back to battery on its own, and reset the trigger. Sometimes it won't go fully in battery but with a punch it usually will.

You're inducing your "problem".

Perhaps the store where you bought the CA Compliant Shield can offer you some instruction to help familiarize you with the features and normal operation of the gun. Is this your first firearm, or at least your first pistol?

While I'm familiar with the Shield pistol as an instructor who has handled and fired them, and as an armorer who has completed the Shield class (as a M&P pistol armorer), I couldn't pretend to know what's happening with your Shield without being able to observe you and your Shield in person.

Typically, over the long run, close to 95% of "gun problems" experienced by firearms owners/users are the result of something the owner/user did while handling, manipulating and using the gun. Something done improperly (albeit unknowingly), or something not done (but ought to have been done).

Yes, the short and robust recoil spring assembly in the Shield, and the short slide travel distance and compact mechanical functioning, can offer difficulties to some new owners/users. We saw that among our fair share of new Shield owners in past years. To be fair, though, it's also not uncommon to see it happen with virtually any firearm model that's "new" to the owner/user. Not just the Shield.

Don't think you've discovered something new.

Just some thoughts.

[sweetfoal]

Good to know the problem I've experienced is not uncommon. Guess most of my ways of handling pistol were developed with Glock. As I mentioned I've used glock (19, 26) for a long time, presumed I would continue the same habits with all pistols with similar design (striker fired, semi...). I agree it's generally a good practice to just do everything by the book. Now I'm really curious and going to read the manual cover to cover.


Thanks for the suggestion.