M&P .40 kabooms?

[Hmac]

This post is making the rounds on various gun forums....

This is now the fourth report of an M&P Shield 40 going KaBoom. This incident was with factory ammo.
Previous recent KaBoom was with Federal factory ammo.

http://smith-wessonforum.com/smith-wess ... aboom.html

[Lumpy]

Owee! Makes me glad my .40's a Beretta 90-TWO.

[brad3579]

Almost bought one but kind of glad I didn't now.

[Seismic Sam]

Quoting a knowledgeable source, the apparent cause of Glock 40 kabooms, which are far more than anecdotal, is the lack of case support at the bottom of the barrel, and NOT dependent upon occasional occurrences of bullet setback. Seeing as you were shooting factory ammo, the setback theory due to low case mouth tension with a handload doesn't fly anyway. What does the breech end of a barrel from one of these guns look like?? Apart from that, the rear picture is interesting, and the rear slide rails appear to be a single piece of metal that is fixtured/molded into the polymer frame. If that piece comes loose during firing, it could allow the barrel to unlock from the slide and a lot of the pressure to come back and destroy the frame as it did. Was this the result of an injection molding error, or perhaps a lack of adhesion between the metal part and the polymer frame???

[TTS]

KB's happen in everything. There are more .40 glocks than just about any other .40 caliber pistol in existence.

If you don't believe me, take a look at the pics.
https://www.google.com/search?q=kaboom+gun&espv=210&es_sm=119&source=lnms&tbm=isch&sa=X&ei=dA8AU97pMqi9yAH4mIG4Ag&ved=0CAkQ_AUoAQ&biw=1280&bih=589#imgdii=_

[Hmac]

Sometimes KBs are due to a bad handload, sometimes a bad factory round, sometimes a factory design defect. The question is why this has happened 4 times in a relatively new pistol design. It makes people wonder whether or not the .40 Shield is more prone to kabooms that it ought to be.

[TTS]

Sometimes KBs are due to a bad handload, sometimes a bad factory round, sometimes a factory design defect. The question is why this has happened 4 times in a relatively new pistol design. It makes people wonder whether or not the .40 Shield is more prone to kabooms that it ought to be.

Agreed that it is odd to have so many in a new pistol. I did see that 1 was with old corbon and the other with underwood 135gr +p... Also, I wonder of it could be some over pressure ammo? With manufacturers pumping out ammo so fast QC can slip. I have heard of an abnormal number of squibs with WWB lately.

[PHATSPEED7x]

Never been a fan of .40 cal because of the reports of boom... yikes..

Sent from LG G2

[Seismic Sam]

KB's happen in everything. There are more .40 glocks than just about any other .40 caliber pistol in existence.

If you don't believe me, take a look at the pics.
https://www.google.com/search?q=kaboom+gun&espv=210&es_sm=119&source=lnms&tbm=isch&sa=X&ei=dA8AU97pMqi9yAH4mIG4Ag&ved=0CAkQ_AUoAQ&biw=1280&bih=589#imgdii=_

Thanks for the link to all the kabooms - that will save me time in the future, and yes, kabooms do happen in every gun, BUT in a vast majority of these pictures handloads were involved, and really bad or stupid handloads at that, like using Bullseye instead of Benchrest, because the idiot doing the loading only remembered that the powder started with a "B". Oh, hey, Bullseye!! That's the one I was thinking of...

40 Kabooms do fall in a class by themselves, and as I said above, some people with the right equipment have looked into this, and found that bullet setback as a cause appeared to only affect Glocks because of the lack of chamber support. That may have changed with the proliferation of partially polymer compacts and sub-compacts that can handle a 40, and as I said before, it appears to me that the rear rails on the frame maybe getting pried up out of the frame with stiff loads, but that's just a guess from a small picture. My gut says this may be the tip of a real recall, and with manufacturers putting out new models left and right as fast as they can with new structural component configurations to keep up their market share in this area, the situation is ripe for a "too much, too fast" design.

[TTS]

Thanks for the link to all the kabooms - that will save me time in the future, and yes, kabooms do happen in every gun, BUT in a vast majority of these pictures handloads were involved, and really bad or stupid handloads at that, like using Bullseye instead of Benchrest, because the idiot doing the loading only remembered that the powder started with a "B". Oh, hey, Bullseye!! That's the one I was thinking of...

40 Kabooms do fall in a class by themselves, and as I said above, some people with the right equipment have looked into this, and found that bullet setback as a cause appeared to only affect Glocks because of the lack of chamber support. That may have changed with the proliferation of partially polymer compacts and sub-compacts that can handle a 40, and as I said before, it appears to me that the rear rails on the frame maybe getting pried up out of the frame with stiff loads, but that's just a guess from a small picture. My gut says this may be the tip of a real recall, and with manufacturers putting out new models left and right as fast as they can with new structural component configurations to keep up their market share in this area, the situation is ripe for a "too much, too fast" design.

Sam, do you know of any scientific testing that has been done related to bullet setback? The link below shows anecdotal evidence that it may not be much of an issue. However, I generally don't like to make assumptions based off anecdotal evidence.
https://plus.google.com/+luckygunner/posts/CiVxdHvWjYS

[Cuda66]

I believe he was running those hot-hot-hot Underwood 135's when the gun detonated.

I'll put money on it being an ammo problem more than a Shield problem.

[TTS]

I believe he was running those hot-hot-hot Underwood 135's when the gun detonated.

I'll put money on it being an ammo problem more than a Shield problem.

That was my first thought as well but there were 3 others in the last few months with other factory ammo (on the S&W forum).

[mmcnx2]

I would agree, bet these end up being ammo. If you look 40 from major manufactures the standard is about 1100fps, some from smaller manufactures or labeled +P is running 1300fps or even high. 40 chamber pressures are up there already, playing on the high end would not take much of a variation to spike pressure and cause an kaboom. I'll hold out to see what ammo was being used and what the engineers say is happening to these pistols.

The reality is these are major gun manufactures and they spend a small fortune on R&D, the probability of them making a major FUBAR is relatively low, but not impossible. The other side is all the little re-loaders going commercial may not have the QC that the big boys do. I mean a guy with a Dillion 1150 in his garage is not someone I'm risking my life with.

I see enough antics at the range every time I go, most failures I've seen have been operator stupidity, either handling, ammo or a combination.

[Hmac]

Are we seeing more .40 kabooms these days? I visit a lot of gun forums and don't see that at all. The incidence of kabooms in the .40 Shield is starting to stand out.

[mmcnx2]

I think you are seeing the Shields for a few reasons.

They are new and guys that blow stuff up do it quick, there seems to be more guys pushing loads(this includes some of the small commercial vendors), no one is going to admit they screwed up.

Years ago some guy blew up a colt 45, the first assumption it was the idiot with his finger on the trigger. Nowadays the first blame has to be the gun, then the ammo, then the moon phase, then guy in the next lane...never the idiot.