Cannot lock the slide on new M&P Shield

[datx]

Hi everyone. I'm new to the forum, and was hoping to get some help on my new M&P Shield 40. I just got it from my FFL dealer earlier today. Was just about to give it a quick cleaning before I try and take it to the range tomorrow, but I noticed I can't lock the slide back.

This is what I have tried, first I release the mag, then I rack the slide back and try to lock it in place. I just noticed when I do this, I can see the little "piece" that goes up and should hold the slide from going all the way back forward, but the slide doesnt go back far enough.

Also, I was expecting that the slide will lock in place with an empty mag in it, but unfortunately does not. Im pretty sure it should and just want to double check with anyone else that has the Shield. Thanks for any help or advice.

[ken158]

Sounds like slide was removed and not replaced correctly. Give it another try...

[datx]

ken158 - Yea, trust me. I have tried and tried. Im charging the battery to my digi cam so that I can post up photos soon. I bought the Shield online and unfortunately can't simply exchange/return it, or I would.

[robotoid]

I had the same trouble on my first takedown/reassemble. Recoil spring was not seated properly when I put the slide back on. Use the sear disconnect and push the takedown lever down while simultaenously sliding off the slide. Reseat the recoil spring against the barrel.

[datx]

Ok, I finally got it. Once I rack the slide all the way back (or at least I think its all the way back), I gave it a harder pull at that point, and got it to lock. Sorry guys, I really thought there was an issue with my new Shield. It just didnt seem right. I have not had to rack the slide that far back or hard before on any of my firearms, so I got a bit nervous that my Shield had issues. Again, sorry for the false alarm.

[MichiganScott]

Originally Posted by datx

This is what I have tried, first I release the mag, then I rack the slide back and try to lock it in place. I just noticed when I do this, I can see the little "piece" that goes up and should hold the slide from going all the way back forward, but the slide doesnt go back far enough.

They will only lock back with an empty mag in place or if you push up manually on the slide lock.

[fuzzymcnab]

Scott,
Could you please confirm. The Shield does not lock open on the last shot?
Thanks,fuzzy

[Smitty357]

Originally Posted by fuzzymcnab

Scott,
Could you please confirm. The Shield does not lock open on the last shot?
Thanks,fuzzy

Mine locks open after the last shot. Has every single time.

[Houdini1953]

Originally Posted by fuzzymcnab

Scott,
Could you please confirm. The Shield does not lock open on the last shot?
Thanks,fuzzy

If this is happening try using both magazines unloaded and rack the slide fully to the rear if it does this with one magazine and not the other then it is the magazine and probably a weak spring in the magazine not pushing the follower up against the slide lock and thereby keeping the slide locked back after the last round.

[patbelly]

Originally Posted by fuzzymcnab

Scott,
Could you please confirm. The Shield does not lock open on the last shot?
Thanks,fuzzy

The Shield does lock open on the last shot of a magazine.

[pistol]

My Shield 9mm is brand new and I had a terrible time locking the slide back also on take down and reassembly. I just don't have the strength to push the lock up and get the slide back far enough. I am use to Bodyguard 380 which is easy. My husband can do it fine but it is so very stiff for me. My wrists are killing me. I hope it gets better when it is broken in. Otherwise I love it!

[dullh]

Mine locks open, too...on empty mags, on hand cycling, etc...but I have noticed after reassembly if you don't get the back of the guide rod situated perfectly the slide will not travel all the way to the rear, and will not lock. The slide stop in the Shield is set up to where it only engages a few thousands short of the end of slide travel.

[Donmc01]

Mine locks back fine after last shot as well without an empty mag in place. I could not be more pleased with my Shield for it's intended purpose, CC. I am confident mine will go "Bang" if necessary.

Don

[gdauth]

Originally Posted by pistol

My Shield 9mm is brand new and I had a terrible time locking the slide back also on take down and reassembly. I just don't have the strength to push the lock up and get the slide back far enough. I am use to Bodyguard 380 which is easy. My husband can do it fine but it is so very stiff for me. My wrists are killing me. I hope it gets better when it is broken in. Otherwise I love it!

How are you grasping the slide when you try to rack it?

[OhioLefty]

It's new and will loosen up. I had to replace the Recoil Spring Assembly on my .40 Shield and the RSA Smith & Wesson was really stiff. I could lock back my old RSA really easy but the new one was so stiff I could not get it to lock back. After I finally got it locked back, I left it that way over night and now it's fine.

Good luck...

[Willie B]

Originally Posted by pistol

My Shield 9mm is brand new and I had a terrible time locking the slide back also on take down and reassembly. I just don't have the strength to push the lock up and get the slide back far enough. I am use to Bodyguard 380 which is easy. My husband can do it fine but it is so very stiff for me. My wrists are killing me. I hope it gets better when it is broken in. Otherwise I love it!

Try pulling the slide rearward while pushing the frame/grip forward at the same time. This seems to work for folks who don't have lots of wrist strength.

Racking a Slide Like a Lady - YouTube

[Cokeman]

Next time it does that, take the slide off and spin the spring and guide rod and try again. Once you can pull the slide back easily and lock it back, you are ready to go shooting.

[glocksocks]

Is that normal for the RSA to have to be rotated to get it to work properly??? I'm having this same issue. I had to install my RSA about 10 times before I could rack it all the way back. Here's a picture of the top of my RSA... I swear it doesn't look right...

[Cokeman]

I think the spring should be wound tighter against the guide rod so it can't move side to side. Maybe the guide rod could be thicker?

[Robotech]

Originally Posted by glocksocks

Is that normal for the RSA to have to be rotated to get it to work properly??? I'm having this same issue. I had to install my RSA about 10 times before I could rack it all the way back. Here's a picture of the top of my RSA... I swear it doesn't look right...

Both of mine, the original and the replacement S&W sent, sit flatter against the forward stop than your picture shows, but I don't think that end is as much of a problem. See if you can reposition that end of the spring on the forward stop, and get it to sit flatter.

On mine, the other end of the spring was bent away from the rest of the spring when they were cut. This forces the body of the spring to bow sharply away from the rod "almost" opposite where the cut end rests on the stop. This results in a "wave pattern" along the rest of the spring.

The trick has been to insert the recoil spring so the wavy spring doesn't interfere when it is compressed as the slide moves back.

[glocksocks]

Originally Posted by Robotech

Both of mine, the original and the replacement S&W sent, sit flatter against the forward stop than your picture shows, but I don't think that end is as much of a problem. See if you can reposition that end of the spring on the forward stop, and get it to sit flatter.

On mine, the other end of the spring was bent away from the rest of the spring when they were cut. This forces the body of the spring to bow sharply away from the rod "almost" opposite where the cut end rests on the stop. This results in a "wave pattern" along the rest of the spring.

The trick has been to insert the recoil spring so the wavy spring doesn't interfere when it is compressed as the slide moves back.

ahh, got ya. Well, I tried to reposition the spring to sit flatter and it's not working. The other side just goes above the forward stop when moving it around. I see what you're saying about the cut on the other side, mine looks the same as your describing. I've put the weapon in jail until I receive the new RSA from S&W. It's like a kid that doesn't take his new toys out of the box. Very hard to resist shooting it. O well, something to look forward to.

[Cokeman]

Keep spinning the spring on the guide rod until you can lock the slide back by hand. S&W has sent a new spring to people that is exactly the same as the one they already have. You might be waiting for one that is no better.

[itr674]

This does not seem right to have to take off and keept spinning a spring till it works! It takes me about five attempts to get the slide back on the S&W 40 Shield--I have other striker fired sub-compact pistols and none even come close to being this difficult to re-assemble...

[glocksocks]

Well, they said they sent my replacement RSA back on 05/28 and I've yet to receive it. I've emailed them 3 times asking for a tracking number or the status of shipment and they aren't responding. It has now been 8 days... Couldn't really find anything on their website about shipping expectations and I really don't want to call but looks like I'll have to find some time during my work day tomorrow to call them. Dangit!

[rforgy]

Mine has a point where you have to push harder, like it is catching on something, to get it all the way to lock.

[pvq]

Just picked up a new Shield 9mm today and have the same issue. I assume it just needs to be worn in a bit. I am no stranger to firearms, but that is the stiffest spring I have ever encountered.

[hpfenning]

Originally Posted by glocksocks

Well, they said they sent my replacement RSA back on 05/28 and I've yet to receive it. I've emailed them 3 times asking for a tracking number or the status of shipment and they aren't responding. It has now been 8 days... Couldn't really find anything on their website about shipping expectations and I really don't want to call but looks like I'll have to find some time during my work day tomorrow to call them. Dangit!

They are closed until Aug 12.

[George9]

Put the last coil in a vice and give it a tad of a squeeze this will allow it to set flat and not want to push off to one side like it is.. If you screw it up you can get another recoil spring from S&W.. Just don't over do it..G

[Hunter991]

Mine is the same. Slide doesnt reliably lock even if pushing the lever.

[robkarrob]

Hey guys, that little cock of the spring is normal. You don't have to try to get the spring to sit flat. That might be an attempt in futility. As soon as the slide starts to go back, the spring gets depressed and will flatten out. It is a coil spring and as such the spring exerts more pressure on one side than the other. You just have to make sure the spring assembly is seated properly and centered. Pretty hard not to get it seated, but being centered is the most important.

If you can't get the slide to lock, make sure the spring is centered. Just a little off will prevent the slide from fully retracting. If your sure the spring is centered, rack it back "hard" fully, a couple of times. Then try the lock and it should be fine.

Bob

[S&WForty]

Originally Posted by robkarrob

If your sure the spring is centered, rack it back "hard" fully, a couple of times. Then try the lock and it should be fine.

Bob

I'll second what Bob said. That worked for me. After a few times, mine doesn't bind anymore.

I was rather steamed at the pistol, so I was a *little* rougher than "hard." That little spring learned who is boss.

[Cokeman]

Mine stopped doing it pretty quickly. The slide always goes on fine now.

[pvq]

I fired my Shield 9 for the first time yesterday. 214 rounds and nearly flawless operation, just one failure to eject at about the 125 round mark. One would think that 214 rounds would sufficiently soften up the recoil spring. After cleaning, it still took me several tries, spinning and centering the recoil spring assembly, before I was able to pull the slide far enough to the rear to engage the slide stop upon reassembly (and move the locking lever back into place). I'm really at a loss with this issue. Once the slide is reinstalled and the locking lever is back in place, the slide retracts far enough to easily engage the slide stop perfectly without binding. It really doesn't make any sense that it should be so difficult to reassemble. I cannot visualize what might be causing the problem.

[mubob1977]

I'm having the same problem with the slide stop/lock on my Shield engaging. I took it out today for the first time and put 100+ rounds through the pistol. When I got home, I decided to clean it. So I field stripped the pistol, cleaned it and th re-assembled the pistol. But the problem is that the slide stop won't catch when I cycle the pistol. I've taken apart and re-assembled it several times now, yet I still can't get the slide stop to engage.

Any thoughts!

[glocksocks]

Originally Posted by mubob1977

I'm having the same problem with the slide stop/lock on my Shield engaging. I took it out today for the first time and put 100+ rounds through the pistol. When I got home, I decided to clean it. So I field stripped the pistol, cleaned it and th re-assembled the pistol. But the problem is that the slide stop won't catch when I cycle the pistol. I've taken apart and re-assembled it several times now, yet I still can't get the slide stop to engage.

Any thoughts!

It's the RSA, I had S&W send me a new one, you can see my comments previous in this thread about it. The new RSA was better but if I do not install the RSA a certain way, it's impossible to get it to slide back far enough to lock. Play around with it, you'll find the way the RSA needs to be installed that will allow the slide to lock back. Funny thing, through all of this, never had a failure with this weapon in operation... In other words, it'll more than likely be fine, mine is and have the same issues you're having while hand racking the slide

[Pete S]

Originally Posted by mubob1977

I'm having the same problem with the slide stop/lock on my Shield engaging. I took it out today for the first time and put 100+ rounds through the pistol. When I got home, I decided to clean it. So I field stripped the pistol, cleaned it and th re-assembled the pistol. But the problem is that the slide stop won't catch when I cycle the pistol. I've taken apart and re-assembled it several times now, yet I still can't get the slide stop to engage.

Any thoughts!

I have the same difficulty. When slowly pulling back the slide there is a point of resistance that's short of the slide stop by about 3/8" and to slowly pull the slide past that point to full retraction requires Herculean strength. If you rack the slide smartly rearward as in chambering a round, you snap past that resistance point rather easily. It's trying to do it slowly that's the bear. What I found by compressing the spring outside the pistol was that once the outer coil on the RSA is fully compressed (about 3/8" from full slide retraction) you then engage the inner "plunger" coil. That's where the extra resistance lives. Mine seemed to be worse rather than better after 200 rounds on my new Shield and I attribute that to residue getting in the plunger. I put a few drops of CLP in the plunger area and smoothed out the stuttering slide real nice.
You may want to give the spring a solvent bath to remove excess powder then a drop of your favorite oil and you're in business.
Pete

[Lockback]

Originally Posted by datx

Ok, I finally got it. Once I rack the slide all the way back (or at least I think its all the way back), I gave it a harder pull at that point, and got it to lock. Sorry guys, I really thought there was an issue with my new Shield. It just didnt seem right. I have not had to rack the slide that far back or hard before on any of my firearms, so I got a bit nervous that my Shield had issues. Again, sorry for the false alarm.

I had the same problem with my Shield the first time. Luckily, I could call a buddy of mine and we worked through it.
The slide lock tab is to the rear of the release lever, so you have to pull the slide back further than you first think. And the positioning of the recoil spring guide is critical, apparently; otherwise the slide won't go far enough back ...

[potguy]

I just wanted to thank you for posting the solution to this! I just brought mine home and had the same problem. I have a glock and the slider lock is very different.

I love my M&P Shield, just tricky with slider lock. It gives you the impression the lock should go into the hole that is the same size as the lock. I was ready to take my gun back. Boy they would have looked at me pretty funny. All I needed to do is pull the slicer ALL THE WAY BACK, it locks every time that way.

Thanks again,

Ernie

[CaptRon956]

The shield is a sub compact semi auto, its susposed to have stiff springs for proper operation.... In time you will build up some strength in your hands from using it, believe me. Oh & I suggest picking up a Uplula mag loader... You're gonna need it.

[ldoug2]

Seems like a big problem that should be so simple
Shouldn't have to hunt, keep turning spring to find "sweet" spot

[ldoug2]

Shouldn't be that hard to fix. Spinning spring till u get it right seems a bit random

[Stratajema]

Originally Posted by ldoug2

Should have to hunt, keep turning spring to find "sweet" spot

Turning the recoil spring assembly to find the "spot" that allows the slide to fully recoil is the biggest myth about the Shield. The recoil spring assembly is out of spec and needs to be replaced.

There is not one word in the manual about turning the recoil spring. Not one word.

[elvisimprsntr]

My new Shield 9 out of the box, I had trouble locking the slide back and even releasing the slide without pulling it back slightly. Once I put 50 rounds thru it and added a little oil, the slide and release are much easier.

[alleycat7002]

Mine worked great out of box.

[Horn]

Originally Posted by pistol

My Shield 9mm is brand new and I had a terrible time locking the slide back also on take down and reassembly. I just don't have the strength to push the lock up and get the slide back far enough. I am use to Bodyguard 380 which is easy. My husband can do it fine but it is so very stiff for me. My wrists are killing me. I hope it gets better when it is broken in. Otherwise I love it!

Go to Walmart and in the tools department locate the Mechanic
gloves. They're black and very thin. You may need the small size.
Use these (or some that's similar) to practice racking it at home.
Also, try holding tightly with your weak hand and pushing sharply
with your strong hand.
Enjoy your pistol.

[chele519]

It was suggested to me to leave the gun with the slide locked back for a bit. It worked like a charm, no problem with it now.

[XD40inTX]

This has obviously been a problem for at least three years now. It's probably been a problem since the Shield went into production--and yet, S&W has done nothing to correct it. That's very disappointing.

My wife and I both have concealed-carry permits, so we own four other guns--two XD40s (hence my screen name) and two Kimber 1911s. NONE of the other guns have this problem, but both of our Shields have had it since new in the box.

My wife wants to trade hers on a Kimber Ultra Carry II. I think I'll trade mine, too. I'm tired of fooling with S&W.

[ldoug2]

I've locked mine back, shot few hundred rounds. It's still not right. I've contacted S&W again today to fix it or refund. We will see.

[martybee]

The issue with "Slide Lock-back" seems to be very prevalent with the Shield. I had the same problem with mine when new. As datx said in post #5, "Once I rack the slide all the way back (or at least I think its all the way back), I gave it a harder pull at that point, and got it to lock". It just takes that extra little effort to pull back enough to get it to lock!
When I first got my Shield9, I was so disappointed with it that I came close to getting rid of it! I have almost 1,200 rds. through mine now and it is as sweet a piece as you will ever find. I am troubled with RA as I am 84yrs. old, but still am able to shoot weekly at my local indoor range and hope to continue for some time to come.

mb

[Sigsavvy]

I had a problematic RSA when I bought my Shield 40 about a year ago. I called S&W and didn't accept the "shoot it a bunch" response. I told them that the spring was defective and they ended up shipping me a new one. That new one worked every time and I didn't worry about finding that sweet spot anymore.

I just traded the Shield 40 for a 9 and found the RSA to work perfectly (although I still think it's the weak link in an otherwise awesome design).

It sounded like they are not on backorder like they used to be so I would just request a new RSA and go from there.