M&P Shield .40 Blow Up

[Rastoff]

I've been to the range many times with many people. Never have I confused my ammo with someone else's. If he said he fired his own stuff, I believe it.

Even if it were due to a reload, what are the odds that it was just one? I mean, if he screwed up one round, he probably screwed up more. They fired a bunch of the other stuff with no trouble. So, I don't think it was a reload problem.

I'm more inclined to believe it was a weak, unsupported case.

 

[Roger S&W]

I only wondered because I know my 9MM Shield will release the striker if the slide isn't all the way forward. It will release the striker if the slide is about 1/8" back. I admit it don't know at what point the striker will hit the primer, but will release the striker.

I have tried this several times while dry firing, and it happens every time.
My thought was that if the slide wasn't all the way forward, could the firing pin hit the primer hard enough to ignite?
It seems like a recipe for a kaboom if it ignited the primer without the slide locked in battery.

Like I said, I have mimicked the test several times while dry firing. I'm not foolish enough to try it loaded.

You need to immediately send your gun back to S&W with a letter stating this dangerous life threatening defect in your pistol.

 

[Rastoff]

You need to immediately send your gun back to S&W with a letter stating this dangerous life threatening defect in your pistol.

I'm not so sure.

I just did some testing with my gun. If I move the slide back 1/16" it will still release the sear. If I move it back 1/8", it will not.

The key to the danger is "out of battery." If the gun is not out of battery, then it is not dangerous. Being in battery, means the slide is forward and against the chamber. What I noticed in my testing is that at 1/16", the barrel/chamber is still against the slide breech face. If the gun were to fire in this condition, it would work as expected. As soon as the barrel/chamber drops, even a little, it won't fire. This is how it should be.

 

[peterthefish]

I've been to the range many times with many people. Never have I confused my ammo with someone else's. If he said he fired his own stuff, I believe it.

Even if it were due to a reload, what are the odds that it was just one? I mean, if he screwed up one round, he probably screwed up more. They fired a bunch of the other stuff with no trouble. So, I don't think it was a reload problem.

I'm more inclined to believe it was a weak, unsupported case.

The OP stated he may have fired his buddy's reload. If he's not 100%, I'm sure not.

As far as the odds it was just one? Pretty good! Maybe he reloads on a 550 and forgot to index the plate. But I don't think its a double charge - that would probably have been uglier.

More likely he did not quality check the brass prior to loading. .40 S&W isn't like .45 ACP where you can keep loading it until the mouth splits. Especially if you're firing it in a gun that bulges the base of the case. Overworked / brittle brass does not provide the same support that fresh brass does.

One of many reasons that no OEM warrants their gun for reloads. They manufacturer based on SAAMI specs, which do not contemplate overworked brass - it's not reasonable to expect a manufacturer to design a gun that can stand up to every stupid thing done to it.

I agree the chamber is not as well supported as some .40s on the market, but in any caliber there are some guns with more or less support. As long as the chamber support is adequate for fresh factory ammo then the gun is built to do what they say it will do.

 

[peterthefish]

You need to immediately send your gun back to S&W with a letter stating this dangerous life threatening defect in your pistol.

Notsomuch. As already noted, if the barrel and slide are locked up, your gun is in battery, even if the slide isn't fully forward. Probably is locked up with an 1/8" of rear travel.

Even if not, the striker catches the sear as the slide returns forward. As soon as the striker hits the sear it can be released by a trigger pull. However it;

a) would not be fully cocked if the slide is not all the way forward and thus unlikely to pop the primer,

b) if it could even reach it. Which it can't. Firing pin block. Gun has to be fully in battery to disable. Even if the sear releases the partially cocked striker, it will just hit the block.

Try the pencil test noted earlier.

 

[Wildcat66]

As I understand it, .40 S&W rounds are very high pressure, more so than .45 or 9mm. It's pushing the envelope to the limit, so to speak. If one of those goes off outside the firing chamber, especially in a plastic gun, it's going to cause a mess. Good idea NOT to use reloads, if reloads might cause problems.

Very glad you weren't badly hurt Matt. I can't believe S&W failed to see the two cracks, they are extremely clear to me in all your pictures.

I have a 9mm Shield. I have enough bang to control in my Springfield XDm .40 compact, and that's a larger gun though not full size.


From the various pictures posted of busted guns it seems that the .40 Shield is an accident waiting to happen to the person firing it.

Regarding pressure. It is a common misconception that the 40 S&W is higher in pressure than the 9mm. Actually they have identical saami max pressures.

Have been reloading and shooting 9mm in various guns for over 40 years without a mishap.
Just started reloading last fall for the 40 S&W. Shooting it out of a Glock 23 with a Wolf aftermarket barrel. Over a 1000 rounds through it without a hangup.

Nick
West Virginia
Something else is causing these accidents.

 

[B3500]

As I understand it, .40 S&W rounds are very high pressure, more so than .45 or 9mm. It's pushing the envelope to the limit, so to speak. If one of those goes off outside the firing chamber, especially in a plastic gun, it's going to cause a mess. Good idea NOT to use reloads, if reloads might cause problems.
... snipped for brevity...

This is a misconception at least when comparing 9mm and the 40s&w.

9mm and 40s&w maximum pressures are very similar as far as SAAMI recommended pressures go. I believe that reputable ammo manufactures will load only up to the SAAMI maximums.

Please reference this table for SAAMI maximum pressures;

38 SPL 17,000 PSI
38 SPL +P 18,500 PSI

9mm luger 35,000 PSI
9mm luger +P 38,500 PSI

40 S&W 35,000 PSI

10mm 37,500 PSI
45 ACP 21,000 PSI

The 9mm and 40 are essentially the same maximum pressure. There is no official +P specification for 40S&W.

So what we may be seeing are the results of either bad ammo loaded outside of spec, bad brass, high primer, differences in the chamber specification causing the round to fire while not fully chambered, chamber is not fully supporting the cartridge, barrel materials or quality or perhaps a combination of several things.

It's not that the 40 S&W round by itself is inherently some kind of high pressure cooker waiting to blow up in your hand. At least it is no different than the 9mm is.

 

[Rastoff]

The OP stated he may have fired his buddy's reload. If he's not 100%, I'm sure not.

You're right. I'm convinced that the OP is convinced that he didn't mix the ammo. But, the mere mention that it is a possibility would cost him a loss in court. So, the door has been opened and can't be closed.

 

[squib load]

I blew up two glocks a year ago.

I owned a glock 23 and really liked it.I was shooting my own reloads and sometimes I would get a setback.at the time I didnt know about the high pressures and the unsuppoted barrel in the 40s.One time in the indoor range my glocked exploded in my hand.I went and got a bar magnet and picked up the metal pieces,and a broom for the plastic pieces.My round exploded just like yours in the rear of the brass.I bought another model 23 and tried to figure out why it failed.I know this was not smart.The following week this one blowed.I went in the new gun area and bought a steel 40 cal para 15/40.I fed it all my reloads.Since that happened I read what will eventually happen to all 40s they will crack.I have replaced the slide on the para but I dont shoot it much.I like my 45 sig and m p shield 9.Squib Load

 

[Muss Muggins]

Nobody took note of this posting? "It is clear the round fired outside the chamber. It looks like the case of the round is being trapped between the chamber and extractor."
Can we please discuss this guys?
Is this an "out of battery" firing? Something different?
The cause of this KaBoom?

If a round is fired outside the chamber, unless it's trapped in a vise, the bullet flies out of the case fairly easily. Only way to blow out the side of the case is for the bullet to be trapped at one obstacle and the rim to be trapped at another, unless the side of the case that blows out is weaker than the crimp holding the bullet in.

 

[Kovariles]

Here are the pics

I have never seen a case fail like that but having seen it in the picture, I would not blame the gun, I would be more inclined to blaim the ammo or the reloader of the ammo. It is very unfair to slander S&W, the cracks in the polymer frame were obviously caused by the gas pressure not contained in the case and barrel.

 

[Kovariles]

Thinking a bit more about it, could it have been a compressed load combined with a heavy crimp? The 9mm Luger case is very short, it would not be too difficult to use up all the space with a high bulk powder and then setting the projectile too far down.

 

[x-cop]

S&W Shield blow up

I just heard about this incident and read all the posts that bring up good valid observations. Right now it is pretty well known that the 40 cal can have disastrous results due its high pressure possibilities if certain things occur. This pretty much like the .45,9MM fires from an unsupported chamber for the most part. When the pressure exceeds a point it will blow right where yours did. I have read and been told by folks who are supposed to know that OAL is a critical thing, and by moving the bullet in by as little as 1/10th of an inch on factory ammo can change the pressure from 40,000 lbs psi to 80,000 lbs psi! This allegedly has been numerous causes for some glock blowups. Feeding the same round into the chamber over and over can move the bullet possibly in. Shooting Glocks with lead can and usually will cause lead build up in the chamber and gun can fire out of battery in some instances. Glock voids your warranty automatically if you shoot reloads or lead thru their guns.
If you did inadvertantly fire your friends reload, did he seat the bullet too deep causing aforementioned pressure problem?
Your complaint on S&W sending the gun back and telling you there was nothing wrong with it is cetainly valid, afraid to say a sign of what is happening in the entire industry with some of these large gun makers.
BTW, the factory Winchester, white box ammo I have has the full brand name on the head. The primers are gold. All winchester primers sold for reloading I get are gold and not nickl coated. They started doing this some years back.
Hope this helps, just my 2 cents worth.
Good you did not get hurt seriously.

 

[Matt Butner]

Just wanted to update everyone on my gun situation. I wish that i could say that the customer service improved but it did not. After sending the gun back i had to call several times and check the status. I finally got a call back saying that everything was checked out and that they would replace the gun. I was excited to hear this and was glad that things were finally nearing the end of this situation.

I was told that i would receive the gun in 4-6 weeks so i waited and then 7 weeks passed. I called two different supervisors and left messages that were never returned. I called every day and never got an answer from them. I then called the customer service number so that i could at least talk to somebody. I was then told that the gun was on back order and they did not know when i would receive my gun.

Needless to say i started getting a little frustrated "again" and called the supervisors number a few more times and never received a call back, so i started calling everyday again. Now at this point i was getting really frustrated so i called the customer service and waited to talk to a rep. I was then given an order number and was told that my gun was shipped.

I just received the gun back and am really glad to have it. This has been going on since February. I am still a little apprehensive about this gun but i am glad that S&W finally came through. I will be shooting the gun this weekend and look forward to it. I really loved my other gun until the mishap. Thanks for all the responses and time you have given this post. I hope that this will never happen again for the ones that may have had this happen, don't give up on the customer service.

 

[Mountain Walker]

Slow Customer Service

Matt:
I think you have to recognize that the factory makes these things in batches and may be making some other models at present time. It may be several months before your model pistol is being made again. This would be a perfect time to ask about sending a 9mm Shield instead! With new loads such as Critical Duty and HST, you have all the performance needed in the 9mm for a small defense pistol. For years I have only thought in terms of 45 or 40 for defense, but technological improvements in ammo have changed the playing field: https://www.youtube.com/watch?v=wJZFZFmBKa0

Even though Smith originally developed the M&P Shield as a police service pistol in 40SW, there have been problems with handling the cartridge in their compact model. Here is a video, take a look at 5:50 for the cracked slide. https://www.youtube.com/watch?v=OLFAt63aNbY

The good news for me is that the Shield was built with the thought of handling the 40SW. Even it it is not fully up to the 40SW, I think it is very well built for the 9mm. BTW, I shot some of the white box 180 JHP and thought they were pretty well stoked, perhaps a little too hot.

 

[Rastoff]

I just received the gun back and am really glad to have it.

Even though the process was long and painful, you got a gun. Others have been denied a replacement.

I'm sorry it took so long. Still, I hope you enjoy the gun you have.

 

[cloudy]

I'm fairly concerned about the possibility of a Kaboom on the Shield 40 so I have neglected to even take it out to the range. From the research I've done on mine, it seems to have been manufactured in mid to late May 2012. I know that the Shields were having issues back then, so I have been looking at selling it. Not sure what to think anymore..

 

[Well Armed]

I'm fairly concerned about the possibility of a Kaboom on the Shield 40 so I have neglected to even take it out to the range. From the research I've done on mine, it seems to have been manufactured in mid to late May 2012. I know that the Shields were having issues back then, so I have been looking at selling it. Not sure what to think anymore..

How much you want for it?

 

[turbo38gn]

I'm fairly concerned about the possibility of a Kaboom on the Shield 40 so I have neglected to even take it out to the range. From the research I've done on mine, it seems to have been manufactured in mid to late May 2012. I know that the Shields were having issues back then, so I have been looking at selling it. Not sure what to think anymore..

So sell it... and move on... are you looking for someone to talk to about it.... I have one of the early models.. zero issues... in fact there were only a few that had issues, and if you read closely and really paid attention you may come to a different conclusion. I see nothing wrong with this gun... if I take any precautions, I would stay away from 180gr ammo...

 

[cloudy]

How much you want for it?

I've had a lot of offers around the 300 mark but I was leaning towards a trade w/ something in 9mm.