M&P .40 kaboom


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0to60
October 27, 2013, 06:12 PM
Here are some pics of my buddy's SW M&P .40 after he fired what we're guessing musta been a double charge. This round was supposed to be 7.5 grains of Power Pistol under a 140 grain MBC truncated cone bullet.

The remains of the case were very tough to get out of the chamber. We had to tap it out with a screwdriver down the muzzle. The case is an absolute mess. Notice how the rim is completely gone. The upper part of the case was forced rearward enough to completely collapse the rim. The frame has been mortally wounded, and many of the small metal parts inside have been broken or sheared off. The extractor was blown completely out, but other than that the slide seems fine, as does the barrel, chamber, ramp, magazine and shooter's hand.

I'm thinking this was definitely a double charge. He said the flash and bang was considerably more than a normal round. He says that a double charge (15 grains of Power Pistol) very nearly fills the case, but it is possible. He reloads with a Dillon RL 550, and this DOESN'T have an auto indexing shell plate, which makes it a bit easier to make this mistake.

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oldillini
October 27, 2013, 06:19 PM
Glad he is okay. Potential for serious injury. He is fortunate. Looks like a new M&P is in order though.

I have been reloading for only a couple of weeks, but I could see how it happens, at least with my set-up. I have to be cautious and keep distraction to a minimum.

44vaquero
October 27, 2013, 06:21 PM
More likely it was bullet set back causing a radical (IE Massive) increase in chamber pressure. 40's can be very susceptible to over pressure due to bullet set back bullet if neck tension is not correct.
Happy that no one was injured!

joed
October 27, 2013, 06:28 PM
More likely it was bullet set back causing a radical (IE Massive) increase in chamber pressure. 40's can be very susceptible to over pressure due to bullet set back bullet if neck tension is not correct.
Happy that no one was injured!
My thougts too. Pretty hard to double charge 7.5 gr of Power Pistol in a case that size.

GaryL
October 27, 2013, 06:28 PM
Wow! Glad he is ok, and thanks for posting that up.

I load on a 550, and whenever possible, choose loads that nearly fill the case for that reason.

JRWhit
October 27, 2013, 06:34 PM
I can't believe his hand is o.k.
Maybe it's the light reflection,but that slide looks bent in the pic.

rsrocket1
October 27, 2013, 06:57 PM
14 grains will fill the case to the rim. I don't think this was a double charge. I agree it was probably too loose a bullet fit that led to a setback. You should take the remaining bullets and see if you can push them in. If you can press them in with anything less than leaning into it with your body, they are probably too loose.

bigfinger76
October 27, 2013, 07:36 PM
That's why I'm not a big fan of light .40 bullets - reduced bearing surface. But I'm surprised a lead bullet would set back like that.

CharlieDeltaJuliet
October 27, 2013, 07:38 PM
Just glad he is ok. Send it back to S&W. They should send a new one with the same serial.

bigfinger76
October 27, 2013, 07:40 PM
That's a joke, right?

Hangingrock
October 27, 2013, 08:05 PM
:uhoh:Warranty S&W I don't think so. They'll have a problem with the use of reloaded ammunition.

Mac45
October 27, 2013, 08:09 PM
Glad your buddy is OK.

sexybeast
October 27, 2013, 09:25 PM
I think it was a double charge. My friend loaded a squib, shot it, chambered another round and shot it. Both bullets exited and the barrel bulged. But the damage was not as bad as that.
If it was bullet setback it would not have been that damaged, especially with a 140gr lead bullet. I shoot those too, probably over 10,000 of them by now.

0to60
October 27, 2013, 09:42 PM
If the neck tension is too loose and the bullet set back, it doesn't seem like pressure could get high enough to blow out the frame. Wouldn't a loose crimp allow the bullet to start moving down the barrel sooner? I would think the path of least resistance would be to push the bullet out the barrel rather than blow out the frame.

Now if the crimp was too TIGHT and the bullet seated too deeply, I could see the frame being the path of least resistance.

The other thing I can't understand about the neck tension explanation is, how is this not more common? Crimping is the least scientific part of reloading. Powder gets measured, bullet seat depth is measured, but crimping seems to be "eyeballed" by a lotta reloaders. If "eyeballing" incorrectly can lead to such a catastrophic result, I'd expect to hear about this a lot more.

Educate me!

Conservidave
October 27, 2013, 10:00 PM
Taper crimping is more of a "Feel" for me, but I load on a single stage. Case mouths can and should probably be measured for proper size. Glad your buddy is OK.

sexybeast
October 27, 2013, 11:04 PM
Well put and well said:
If the neck tension is too loose and the bullet set back, it doesn't seem like pressure could get high enough to blow out the frame. Wouldn't a loose crimp allow the bullet to start moving down the barrel sooner? I would think the path of least resistance would be to push the bullet out the barrel rather than blow out the frame.

Also: Its a light and lubed bullet, large bore, and also lead which accelerates easier.
Good thing is was an M&P and not a Glock. Because then it would be the guns fault!

918v
October 28, 2013, 12:47 AM
I don't think it was either. A double charge would not have allowed your friend to seat a bullet. Bullet setback would not have increased pressure appreciably with his powder. This was prolly caused by a defect in the case head, such as a Crescent Mark caused by brass flowing down the feed ramp which is often ignored as long as the sizer sizes the case enough to chamber.

readyeddy
October 28, 2013, 01:03 AM
I don't know if it was a double charge, but it's not hard to compress a load with the powder close to the rim. I've heard of folks loading 30 06 by using the case as a scoop and filling it up and compressing the load.

Steve C
October 28, 2013, 03:56 AM
40's have been having KB's ever since they where introduced. The cartridge is high pressure (SAAMI max is 35K psi) and the barrels are often not fully supporting. Reloading cases that have been stretched at the base from being fired in less supported barrels known to weaken brass is a hazard, one needs to examine any range pick ups well. Another problem seems to be new reloaders with progressive machines who are more interested in how fast they can produce ammo than how good their QA is. Your buddy learned an expensive lesson in that regard. Hopefully others will learn from his experience.

The good thing is that KB's seldom result in any serious injuries and your buddy wasn't hurt.

steve4102
October 28, 2013, 09:27 AM
I don't think it was "bullet set-back".

http://dailycaller.com/2013/03/05/battered-bullets-does-bullet-setback-matter/

hentown
October 28, 2013, 09:43 AM
I think it was a double charge. My friend loaded a squib, shot it, chambered another round and shot it. Both bullets exited and the barrel bulged. But the damage was not as bad as that.
If it was bullet setback it would not have been that damaged, especially with a 140gr lead bullet. I shoot those too, probably over 10,000 of them by now.

I've loaded and fired over 300,000 rounds through my Glocks...only had one KB, and that was setback-related. The .40 is particularly susceptible to setback-induced KBs.

This is not a .40. Was a .400 Cor-Bon. Was caused by feedramp-induced setback. Slide was ruined; however, Glock took care of me...not free, but cheap.

http://i107.photobucket.com/albums/m294/Walteridus/Port.jpg (http://s107.photobucket.com/user/Walteridus/media/Port.jpg.html)

CharlieDeltaJuliet
October 28, 2013, 11:02 AM
I never said warrantee , I said they will fix it. It will cost a pretty penny, but I bet less than buying a new gun.

0to60
October 28, 2013, 11:30 AM
I've loaded and fired over 300,000 rounds through my Glocks...only had one KB, and that was setback-related. The .40 is particularly susceptible to setback-induced KBs.


How were you able to verify this?

918v
October 28, 2013, 11:31 AM
I don't think it was "bullet set-back".

http://dailycaller.com/2013/03/05/ba...etback-matter/

When Clark double compresses 14 grains of Power Pistol under 124gr bullets in 9mm cases , fires them through a semi-auto pistol, and lives to tell about it there can be no doubt this was neither bullet setback nor a double-charge. Power Pistol is pretty much stupid proof.

I recently resized 3000 once Glock-fired .40 cases through my Redding GRX push-through carbide sizer. Understand the Glock .40 chamber is really big. Cases fired in Glock .40 chambers expand a lot. Current Glock .40 chambers are better supported than earlier ones, but they still big! So when u run one of those cases through a GRX and it's thin carbide insert, you learn a lot about the case. Imagine trying to put your wife's wedding ring on your finger. That's what's happening to a Glocked .40 case as it's being pushed through a GRX die. You get instant feedback through the handle of your press if there are any defects in the case head. I trashed about 100 cases because they felt like a ratchet, like I was swaging a screw. These cases looked normal otherwise. What do you think would have happened one two or three reloads down the road?

sexybeast
October 28, 2013, 01:07 PM
Quote from the article:
Armed with the common knowledge that .40 S&W cartridges are especially susceptible to pressure issues from bullet setback, and that the Glock 22 would blow up if you looked at it wrong,

Read more: http://dailycaller.com/2013/03/05/battered-bullets-does-bullet-setback-matter/#ixzz2j22NOFU2
This seems to be public perception! But no matter what the writer did he could not blow up his gun. Too many people have read that .40 cal is an evil, dangerious, explosive, and badly designed round that should never have been invented.
I have a Gen 2 Glock 22 [pure evil]! and I load the brass over and over and I also shoot lead through it. Some here think I must have a death-wish!
But after at least 10,000 rounds I've had no issues with it or the brass. Of course I find a split case now and then and toss it
I've had a split/ruptured case in 9mm and 45. In the 9 in my g17 the case split/ruptured and gas blew out the mag and cause the trigger spring to disconnect [easy fix]. The bullet seemed very light as it must have bairly left the barrel and the case did not eject and had a rather small hole where the gas escaped.
Look at the M&P 40 pics. It was a double charge that was compressed by a small 140gr lead bullet which does not go that deep into the case. I know because I load thousands of these every year.
Send the gun back to S&W. I know Glock will [if asked] to produce another frame with the same serial #, S&W may also. But just like Glock, Springfield, and others they will probably get you going with a new gun at a reduced price.

918v
October 28, 2013, 01:30 PM
It was a double charge that was compressed by a small 140gr lead bullet which does not go that deep into the case. I know because I load thousands of these every year.

It was not a double charge.

Such a charge would have spilled powder all over the press when indexed. It would have been noticed immediately.

This was a defective case.

0to60
October 28, 2013, 03:48 PM
Maybe not a double charge, but maybe some other type of overcharge. Maybe he was running low on Power Pistol and filled the hopper up with HS6. I wouldn't put that past him.

Correct me if I'm wrong here, but in a locked breach pistol, the barrel and slide move rearward until pressure is low enough for them to safely separate. This happens when the bullet leaves the barrel. I'm assuming the case was intact while the breach was locked. Once the barrel separated from the slide, the primer end of the case was no longer supported and the pressure blasted out the back of it. The bullet HAS to be out of the barrel at this point. So what we're saying is even though the bullet was gone and the barrel is basically an open tube, the pressure was still high enough to blow the case out.

Now let's say the bullet was seated too deeply. The charge ignites in a smaller space, and this leads to MUCH higher pressures. The barrel and slide are still locked together, supporting the case. As the bullet starts moving down the barrel, for each action there is an opposite reaction. The slide/barrel start moving rearward. They can't be rearward enough to separate until the bullet leaves the barrel, because that would imply that the charge is working against the slide MORE than it is the bullet. A locked breach gun is "calibrated" to unlock AFTER the bullet leaves the barrel. The locked slide/barrel move in unison with the bullet; one doesn't outpace the other (or does it?)

So I'm thinking this can't be setback. It seems like the dangerous part of a setback ignition occurrs when the barrel and slide are still locked together. If the chamber/barrel/slide can withstand that, I'm guessing that the worst is over, and once the bullet is out pressure quickly drops to normal levels. For the pressure to be high enough to blow the case AFTER the bullet leaves the barrel, you had to have too much powder.

Thoughts? Corrections?

Eb1
October 28, 2013, 06:26 PM
I'll say this, and probably get flamed to complete char, but IMO the .40 S&W is a dangerous cartridge. It seems that almost every kaboom I read about is a .40 S&W, and the benefit over a .45 or 9mm isn't worth it to me.

I don't recommend .40 S&W to any new auto pistol shooter. Again that is me. I always say go with the oldies: .45, 9mm, .380, or revolver calibers.

I am glad that you were not injured. I hope it never happens again, and I hope to my friends who shoot .40 S&W that it doesn't happen to them. I will not shoot their guns in .40 S&W.

788Ham
October 28, 2013, 06:34 PM
Next time one would try to extract a case from the breech, I'd be more inclined to use a cleaning rod, screwdrivers are better left in the tool box ! A SCREWDRIVER down the barrel of the pistol ? !!! Man, there hasn't been any "Tim The Toolman" shows on TV for awhile, better options available ! :banghead:

918v
October 28, 2013, 07:58 PM
Correct me if I'm wrong here, but in a locked breach pistol, the barrel and slide move rearward until pressure is low enough for them to safely separate. This happens when the bullet leaves the barrel. I'm assuming the case was intact while the breach was locked. Once the barrel separated from the slide, the primer end of the case was no longer supported and the pressure blasted out the back of it. The bullet HAS to be out of the barrel at this point. So what we're saying is even though the bullet was gone and the barrel is basically an open tube, the pressure was still high enough to blow the case out.

No.

The case blew out while the bullet was still in the barrel. If the bullet was out, the case would not have blown.

918v
October 28, 2013, 08:03 PM
Now let's say the bullet was seated too deeply. The charge ignites in a smaller space, and this leads to MUCH higher pressures. The barrel and slide are still locked together, supporting the case. As the bullet starts moving down the barrel, for each action there is an opposite reaction. The slide/barrel start moving rearward. They can't be rearward enough to separate until the bullet leaves the barrel, because that would imply that the charge is working against the slide MORE than it is the bullet. A locked breach gun is "calibrated" to unlock AFTER the bullet leaves the barrel. The locked slide/barrel move in unison with the bullet; one doesn't outpace the other (or does it?)

The bullet accelerates faster than the slide/barrel assembly because it is lighter.

You assume the entire bottom of the case is supported. It is not. About 10% isn't. If there is a defect in that part of the case, it will let go.

Potatohead
October 28, 2013, 08:07 PM
Makes me want to be even more careful. I was just thinkin about switchin to 40 SW. Well, not totally. Maybe need to rethink.

blarby
October 28, 2013, 08:24 PM
HArd to tell due to the case extraction method.........


BUT

This looks like failure at the web.

It just so happens the case failure point was near the weakest part of the entire assembly.

I'm with 918v on this'n.

0to60
October 28, 2013, 08:55 PM
HArd to tell due to the case extraction method.........

In one of the pictures you can see the case still in the chamber before I got it out. The entire bottom of the case is completely gone.

Now, when the slide and barrel are locked, the only part of the case that's not supported is the rim. If the blowout occurred while the bullet was still in the barrel, then the slide and barrel were still locked up, no? I'd expect a crescent shaped hole in the case (corresponding to the portion of the rim that was over the feed ramp). Since the ENTIRE bottom of the case is gone, I'm assuming the over pressure situation continued even after the slide separated from the barrel, which would mean the bullet was out the door. The back of the case wouldn't let go if it was supported by the breach face.

But either way, my explanation or 918v's, I can't see how a deep seated bullet could cause this. I'd think that the pressure overage of a deep seated bullet would be gone before the slide and barrel unlocked.

Brin
October 28, 2013, 09:23 PM
Looks like a squib round to me.:banghead:

IMtheNRA
October 28, 2013, 10:01 PM
I was wondering about a squib as well. Can you check the barrel for a bulge or at least a dark ring inside the bore?

0to60
October 28, 2013, 10:18 PM
I was wondering about a squib as well. Can you check the barrel for a bulge or at least a dark ring inside the bore?

Barrel seems to be in good shape still. No bulging or dark rings.

918v
October 28, 2013, 10:32 PM
Now, when the slide and barrel are locked, the only part of the case that's not supported is the rim.

No.

About 1/8" forward of the rim is unsupported on the bottom at the feed ramp. Most pistols leave this area unsupported to some extent. The case walls are very thick in that area and contain the pressure.

On the defective cases I tossed, that area ratcheted through the GRX die and that told me the case heads were defective.

sexybeast
October 29, 2013, 01:53 AM
It was a double charge. Look at the bottom of the case, its gone. I've seen ruptures at the case web [unsupported area] There is a hole there when it happens and much of the bottom of the case is still there. There is no hole on the base of that case. Its gone! The whole thing!
It was a double charge. probably 50,000 plus of psi.
Keep blaming the design of the 40 cartridge, blame that it was shot in a glock, blame whatever you want. It was a double charge!

0to60
October 29, 2013, 09:44 AM
No.

About 1/8" forward of the rim is unsupported on the bottom at the feed ramp. Most pistols leave this area unsupported to some extent. The case walls are very thick in that area and contain the pressure.

If you look at the pic of the case still in the chamber, you can see that only one half of the part that sits over the ramp is blown out. If it was what you're saying, I'd expect the entire crescent shaped area over the ramp to be gone. In fact, I'm not sure why the pressure would open a small hole over the ramp, and then go on to blow the case head and frame instead of simply opening a larger hole over the ramp. Additionally, the M&P has a fully supported chamber. The ramp doesn't cut a crescent shaped, unsupported area into the chamber at all (I have a 2000-ish Glock 22 that has a very clear unsupported area above the ramp, this M&P is nothing like that at all).

Also, don't unsupported case head failures tend to blow the magazine out of the well? In this case, it really seems like the pressure was so high that merely opening a hole above the ramp wasn't nearly enough. The entire case head and frame had to go also.

Now, would a head head failure cause a larger flash and boom? I'd think it'd definitely feel and sound different, but I can't see how it would cause a larger flash.

steve4102
October 29, 2013, 10:42 AM
It was a double charge. Look at the bottom of the case, its gone. I've seen ruptures at the case web [unsupported area] There is a hole there when it happens and much of the bottom of the case is still there. There is no hole on the base of that case. Its gone! The whole thing!
It was a double charge. probably 50,000 plus of psi.
Keep blaming the design of the 40 cartridge, blame that it was shot in a glock, blame whatever you want. It was a double charge!

If I had any Power Pistol I would load it with 15gr and see if it was even possible. Anyone with PP and a 40 case want to verify if the case will even hold that much powder.

918v
October 29, 2013, 10:42 AM
The MP barrel does not fully support the case. You are discounting the radius at the end of the feed ramp. The case is unsupported in that area.

As to why it would blow that way? Maybe because that was the path of least resistance in that particular instance.

Cases are not machined out of billet. They are swaged out of brass discs. A flaw in the disc will carry over to the finished case. It might not be visible. It might not become apparent during the first firing.

I occasionally see case defects that look like folded layers of brass coming together, kinda like the flaps of a box. There is a very fine hairline where they meet. This is why I just love my stainless tumbler. It brings all these to light. The down side is I throw out alot more brass.

All I'm saying is that a casefull of powder would have been immediately identified during bullet seating. So the double charge theory is unlikely. PP does not spike like other powders so bullet setback is also unlikely. That leaves case head defect as the most likely culprit.

ATLDave
October 29, 2013, 11:03 AM
I've never loaded Power Pistol powder, and don't know anything about its characteristics. Any chance that he had powder bridging in his dispenser, such that the previous cartridge got a half charge and this one a 1.5 charge?

fguffey
October 29, 2013, 11:47 AM
If ‘ifs’ and ‘buts’ were gifts and nuts, we all would have a merry Christmas. I miss Don Meredith.

I was at a firing range with a very disciplined reloader when we noticed a shooter/reloader doing every thing he could to pull the trigger on a S&W Model 66, he could not pull the trigger, he could not pull the hammer back, he could not rotate the cylinder and he could not swing the cylinder out. We unloaded everything we had on the tables and then offered to help. The shooter/reloader had a bullet stuck in the cone of the pistol, the bullet prevented the cylinder from rotating.

We drove the bullet back into the case to free the cylinder, then, to our horror he started loading the pistol with his Dillon newly reloaded rounds, we had questions. We offered him all the ammo he could shoot, we offered to help him with his reloading, we offered to loan him equipment he did not have, we offered to give him equipment he did not have. We offered to have him join us at a reloading secession, meaning we were willing to take his ammo apart that day to check for cases with extra powder or no powder. He packed his bags and left.

He was convinced there was nothing he could do to prevent a CATASTROPHIC EVENTS. We convinced him if he had a CATASTROPHIC EVENT he was not going to have one while he was standing between us.

F. Guffey

http://english.stackexchange.com/questions/47182/origin-of-the-idiom-if-ifs-and-buts-were-candy-and-nuts

ATLDave
October 29, 2013, 11:52 AM
Reloading is just not for everybody. Shooting/handling guns isn't for everybody, either, but it's an even smaller subset who have the mentality to reload correctly.

0to60
October 29, 2013, 12:20 PM
The MP barrel does not fully support the case. You are discounting the radius at the end of the feed ramp. The case is unsupported in that area.

As to why it would blow that way? Maybe because that was the path of least resistance in that particular instance.

Cases are not machined out of billet. They are swaged out of brass discs. A flaw in the disc will carry over to the finished case. It might not be visible. It might not become apparent during the first firing.

I occasionally see case defects that look like folded layers of brass coming together, kinda like the flaps of a box. There is a very fine hairline where they meet. This is why I just love my stainless tumbler. It brings all these to light. The down side is I throw out alot more brass.

All I'm saying is that a casefull of powder would have been immediately identified during bullet seating. So the double charge theory is unlikely. PP does not spike like other powders so bullet setback is also unlikely. That leaves case head defect as the most likely culprit.

I see what you mean and I'm definitely going to check over all my brass for bulging or other obvious signs of stress near the case head. But, after googling case head failures and looking at a lotta pics, I'm just not seeing the kinda destruction that we have here.

I'm not sure HOW much of an overcharge he had, but I'm pretty convinced there was more energy released than that gun is designed to withstand. I know he loads near max (despite my constant warnings). And like I said before, I wouldn't put it past him to have accidentally mixed powders.

Otto
October 29, 2013, 01:25 PM
Anyone with PP and a 40 case want to verify if the case will even hold that much powder.
I checked, the casing will contain 15g of Power Pistol. Can you compress it enough where it will accept a bullet? Don't know, I didn't try.
But with 12g of PP you could.

It seems that newbie reloaders are the common denominator in most Kbooms.

sexybeast
October 29, 2013, 01:25 PM
I know he loads near max (despite my constant warnings). And like I said before, I wouldn't put it past him to have accidentally mixed powders.
Mixed powders? or mixed up powders? Even if he had mixed it up with bullseye or titegroup, 7.5gr would probably not have blown up the gun with a 140gr lead bullet. My load with bullseye was 6.2gr before I became older and wiser. But I never had any problems with it.
So lets see, I guess we could put together the perfect storm here: 7.5gr of a real fast powder with a case that had been shot five times out of a glock and the bullet setting back as it was chambered with the case being just a little out of battery. I can see it!
Actually when you wrote: "despite my constant warnings" you may have implied that he is careless or at a point in his life where he should not be loading any longer. I do know someone like that who blew up a few guns and his family had to take some action. Its sad but it would be much sadder if he ended up in the hospital really hurt.
I shoot alot of 40 with that bullet. Now it does not seem to matter how it happened, but why!

Gamer
October 29, 2013, 02:07 PM
Glad your friend is ok. This post reminds me and hopefully everyone one else who reads it to continue doing saftey checks. Makes me thankful for my powder check die on my progressive LNL. I was considering a 550 vs 650 recently and wondering if I really needed the 5th station to contiunue using a powder check die, maybe I do.

sexybeast
October 29, 2013, 02:11 PM
I was considering a 550 vs 650 recently and wondering if I really needed the 5th station to contiunue using a powder check die, maybe I do.
Not only that but auto-indexing may save your butt too! Get the 650

4895
October 29, 2013, 11:54 PM
Being a lead bullet with a traditionally larger diameter than jacketed, I don't see a reason why neck tension is an issue unless the cases are old as heck and the bullet is too small. Most pistol brass lasts virtually forever until the necks split while resizing. I would bet there is some "duplexing" going on or brass fatigue. What is the headstamp of the brass? Anyone out there have that fancy program to make a SWAG at the chamber pressure with a double charge of PP?

Don't get overwhelmed with reloading. It is so easy a monkey could do it. Resize a case, install a new primer, add a prescribed amount of powder, and squish a bullet on top. Repeat as necessary.

ljnowell
October 30, 2013, 12:37 AM
I know he loads near max (despite my constant warnings)

I am not defending your buddies practices as I do not know him, obviously. That being said, I have loaded a large amount of Power Pistol over the years. It has been my experience that it does perform its best at max or near max charges. I find best accuracy with it at those weights and when shot over a chronograph get the best numbers at near max to max. In me experience its kind of a characteristic of that powder.

0to60
October 30, 2013, 03:29 PM
I am not defending your buddies practices as I do not know him, obviously. That being said, I have loaded a large amount of Power Pistol over the years. It has been my experience that it does perform its best at max or near max charges. I find best accuracy with it at those weights and when shot over a chronograph get the best numbers at near max to max. In me experience its kind of a characteristic of that powder.

That's a great point. The kinda powders that work well in the .40 (slower burning) seem to favor high pressure for a uniform combustion. So, you'll have better luck when you load hot-ish.

We both (my buddy and I) reload range brass that we scavenge. I've never had a problem with .45 and 9mm, but I'm wondering if this isn't such a good idea when it comes to .40.

ljnowell
October 30, 2013, 03:54 PM
We both (my buddy and I) reload range brass that we scavenge. I've never had a problem with .45 and 9mm, but I'm wondering if this isn't such a good idea when it comes to .40.

I dont mind max effort 45acp in range brass, its so low pressure and heavy brass. In 40 though, all my reloads are lead bullets and nowhere near max. I use AA#5 for 40.

bronco_buster
October 30, 2013, 05:07 PM
We both (my buddy and I) reload range brass that we scavenge. I've never had a problem with .45 and 9mm, but I'm wondering if this isn't such a good idea when it comes to .40.

I'm R E A L squeamish about range brass in 40sw. I find 90% was likely ejected from a glock--noting the characteristic bulge near the web and the rectangular firing pin strike. I pass them through the Lee FCD "Bulgebuster" and the range of pressure required to iron out those bulges is quite wide. Some pop right through, but I've had others where my 7 year old daughter will hang on the handle of the Redding T7 and the brass will not advance...that is, until I give it a heavy handed push. There is definitely a night and day difference between the brass from an M&P chamber and the Glock...I think everyone will agree. What I've noticed is that after resizing a 40SW from my own Gen 4 G23...it will stick out of the LE Wilson case gage (minimum SAAMI specs) but drop right into the G23 chamber. If dropped in my M&P 40 Pro, it will stand proud compared to a factory case. I can't get calipers in there to measure it, but its noticeable on close inspection. If I run it through the bulge buster, it will pass the LE Wilson gage. If, on the other hand, I try the hardest to bulge bust brass from *presumed* Glocks, ie range pick up brass, which, by the way have already been run through the resizer then through the bulge buster, then those most difficult to size cases will not even pass the LE Wilson gage...unless I pass them through the full length resizer again. So it becomes a full length resize--bulge bust--full length resize to get them to pass the gage. The amount of work hardening on that bulge has to be tremendous and I don't have a lot of faith in the web's ability to hold up to 40SW pressure after that much working of the brass. The cases fired from the M&P after a normal resize will plunk into the LE Wilson case gage and any of my other 40sw chambers without issue, never had to bulge bust any of them. I've now got range pickup *Glock* brass marked in separate containers from the brass that I've run through my M&P and G4 G23 that I KNOW is once fired. I had high hopes for the G23 barrel...its damn accurate...and it appears supported when compared to Gen 2...but I'm still disappointed that the 40SW barrel in the 4th generation G23, at least the one I have, as it will still bulge brass despite looking "supported" when compared to previous generations.

I would bet the brass that was reloaded by your buddy had a weak web from overworking a bulge to get the brass in spec...That's obviously only my theory, I'm certainly not an expert in reloading, but I've been at it for years and have found that "discretion is the better part of valor." And I've found out why purchasing "range pickup" or "once fired" 40sw brass is generally only a good deal if its FREE. I'm universally disappointed when I buy 40sw brass online...its almost all "Glocked"...especially the "once fired on a police range" :uhoh: Does he know the history of that case?

sexybeast
October 30, 2013, 08:44 PM
OK, its true. Glocks are to blame for all the worlds evils if you are are a reloader. I knew it would not be long till a glock was blamed for another gun blowing up.
Time to put the waders on, its getting deep.

Hondo 60
November 1, 2013, 01:12 AM
To the OP:
You didn't say in the original post if all involved were OK.
I hope they are.

My condolences on the gun.
I've had it happen to me as well.
Sucks when you kill a handgun. :(

Ridgerunner665
November 10, 2013, 09:51 PM
I don't think you can double charge any semi-auto round with Power Pistol powder...and I know for a fact that you can't get 15 grains of it in a 40 case...not with a bullet on top.

I'm betting it was weak brass...loaded one too many times.

Power Pistol is pretty much idiot proof in semi-auto pistol rounds, it usually fills the case (and that defends against setback)...about the only way it could possibly seriously mess up is if you had prefect storm of sorts...too much powder, but still enough case left to seat the bullet just deep enough to get the round to feed, partially chamber....and fire out of battery.

ArchAngelCD
November 10, 2013, 10:32 PM
I'm not an expert on the 40 S&W or Power Pistol but I'm not sure you can get 15gr of PP in a 40 S&W case and if you can I can't see you seating the bullet.

How come every time we hear about a KB either the 40 S&W or a progressive press are involved and most time both are involved? Can anyone say "powder check die" or "powder cop" by any chance? Penny wise and dollar foolish, now he has to buy a new gun and he's lucky he isn't missing anything important like a finger or two or even an eye.

It's careless stuff like this that gives reloading a bad reputation. :rolleyes:

gamestalker
November 10, 2013, 11:19 PM
Without knowing just how careless this individual is when reloading, it is impossible to determine exactly what happened. According to the OP he is not cautious, therefore it's just as likely caused by a wrong powder, bullet set back, a double charge, or what ever. Actually there is only one primary reason for KB's, failure to follow safety protolcol is all it takes.

GS

Ex
November 11, 2013, 12:27 AM
Many of my powders I choose specifically for case fill. IE... for .40, I use Longshot. If I were to do ONLY a 20% overcharge, powder would be spilling over the top of the brass.

I have long thought about mounting an LED light on my press JUST so I get a well lit look into EVERY case.

Glad the shooter came out of this un-scathed!

Taterhead
November 11, 2013, 12:59 AM
Sometimes the most simple answers are the most obvious. It seems clear that this was an excessive powder charge. It might not have been a double charge, but short-stroking the press can cause a partial powder load. Follow-up with a full charge, and now you've gone nuke.

The simplest preventive medicine for this is to know the powder that's in the hopper, and to visually inspect the charge before placing a bullet. Not fancy. Just basics.

Another long shot possibility is the potential for a foreign body to be in the case (bug nest, stone, dirt, glob of cleaning media and polishing ointment, etc.


Glad nobody got hurt.

Jim K
November 11, 2013, 01:28 AM
That might be caused by bullet setback if your friend stood around hammering bullets down into the cases, but it looks like an excess charge to me, and pretty typical at that.

Jim

SDGlock23
November 11, 2013, 09:14 AM
I would bet to say it was bad brass, seems overly obvious doesn't it. 7.5gr of Power Pistol with a 140gr lead load isn't hot by any means, but if more powder was accidentally put in, that could cause it too.

Reason I mention bad brass is that I've had two experiences with case-head separations. First was with a .40 XDm, and the load was warm yes, but the once fired brass I was using, well I shouldn't have used. I still have the piece of brass today, and it looks much like what the OP posted, torn in two. However the gun didn't break, just the case so no harm done, the mag came flying out too...although it was an attention getter and it did soot up my hand a little.

Second time it happened was with a Glock 10mm, although the the case didn't completely separate in two, it was about halfway torn. Mag came flying out, but otherwise no damage. Brass was some old funky looking Winchester brass. The load wasn't particularly warm, which is why I blame the brass. Hopefully I've learned, if the brass looks questionable and/or old, don't use it.

I've shot and loaded thousands of .40's through Glocks, even with well used brass that I probably shouldn't have used, but it just takes one weak piece of brass to do it, fortunately those are few and far between. The .40 isn't the problem, that's another myth that just needs to go ahead and die, there's nothing dangerous about, at least nothing more so than any other cartridge.

Here's a pic of the brass from my XDM .40 case head separation:
http://imageshack.us/a/img198/6264/8ep2.jpg

grandpawj
November 11, 2013, 02:26 PM
I been thinking about this one a lot. Especially since I have a Gen4 model 22 Glock. I'll just show some picks I have taken and wondering, "Where is the part of the brass that's not supported?" (A brass is hard to tear into, but I finally ground one down.)

ArchAngelCD
November 11, 2013, 04:20 PM
I been thinking about this one a lot. Especially since I have a Gen4 model 22 Glock. I'll just show some picks I have taken and wondering, "Where is the part of the brass that's not supported?" (A brass is hard to tear into, but I finally ground one down.)
I think Glock has "fixed" the unsupported case problem. (but I could be wrong) The older Glocks had a partially unsupported chamber like this:
http://i178.photobucket.com/albums/w260/lugerman_album/chamber.jpg

Eb1
November 11, 2013, 05:28 PM
So the Gen 4 Glock 26 has a fixed this problem?

wally
November 11, 2013, 08:26 PM
I been thinking about this one a lot. Especially since I have a Gen4 model 22 Glock. I'll just show some picks I have taken and wondering, "Where is the part of the brass that's not supported?"

Your photos do a great job of making sure you can't see that area! Check the photos in post #66

tightgroup tiger
November 11, 2013, 08:52 PM
That looks to me like it fired out of battery. Like it fired before the slide completely closed.

I saw this at range I shoot at just 2 weeks ago. Someone let another shooter fire his glock and the slide didn't close on the round the whole way. The shooter kept forcing it and it finally went off.

It has the exact same results as OP's photos in his first post. I didn't think it was possible to make one fire if the slide isn't completely closed but he managed to do it. He didn't know much about guns, he was new to them and didn't know he was doing anything wrong. He kill that guy's glock also.

After we all went over the pieces of the Glock, looked at the brass and talked to the new guy that blew it up and he admitted to forcing the trigger and hitting the slide forward really hard, our consensus was that the round didn't chamber the whole way and it fired out of battery.

grandpawj
November 11, 2013, 11:47 PM
Wally, can we see your picture of your Gen4 G22 barrel with a round in it?

jim8115
November 14, 2013, 12:16 PM
I am not a gunsmith, so explain to me... how can a case that is expanded like that around the entire circumference, be anything other than an out-of-battery problem?

JIM

Lj1941
November 15, 2013, 06:24 PM
Squib followed by a good cartridge fired behind a bullet stuck in the barrel would be my uneducated guess.An M&P is not a Glock.

sexybeast
November 15, 2013, 07:12 PM
Squib followed by a good cartridge fired behind a bullet stuck in the barrel would be my uneducated guess.An M&P is not a Glock.
__________________

Nope. That would result in a big bulge somewhere in the barrel at the least. Or a split barrel at the worst. Seen a few squibs, before we all could scream "STOP"!!!, the shooter chambers another and pulls the trigger.
The original post he stated that the barrel was fine.
It was an overcharge, double charge [which I now agree would be hard to do], or shot out of battery.

DILLONHELP
November 21, 2013, 12:28 PM
Here is a chart, from this web page, which shows measured pressure changes with 40 S&W using a 180 grain projectile.
http://www.greent.com/40Page/ammo/40/180gr.htm


Overall Length
Pressure
1.140" 26,195 psi
1.130" 27,521 psi
1.120" 29,079 psi
1.115" 29,924 psi
1.100" 32,900 psi
1.075" 39,641 psi
1.050" 50,954 psi
1.040" 57,926 psi
1.030" 66,890 psi
1.020" 80,345 psi
1.010" 101,286 psi
1.000" 138,744 psi

Standard OAL for the .40S&W is 1.120" ... table data from "Handloading" by Charles E. Petty, American Handgunner Jan/Feb 1998, p41.

YMMV, but it is verifiably possible to KB a handgun due to the increased pressures generated by bullet setback.

bds
November 21, 2013, 03:24 PM
Good post DILLONHELP.

While most reloaders are diligent about preventing doublecharged case or squib round (no powder or insufficient powder charge), I do not see as much diligence for checking neck tension.

Simply pushing on the bullet against the bench top is not adequate as this does not duplicate the forces involved while the slide cycles to feed/chamber a round.

IMO, measuring the OAL/COL before and after feeding the test round from the magazine and releasing the slide without riding it is a better check for neck tension as any neck tension issue will translate to decrease in OAL/COL that can be measured/quantified.

Potatohead
November 21, 2013, 04:19 PM
You would really need to check every round though wouldn't you??? Wondering because

I'm quite paranoid I don't have sufficient tension whenever Im loading.

I push on cases/bullets until my hands and fingertips are very sore.

sexybeast
November 21, 2013, 05:53 PM
Overall Length
Pressure
1.140" 26,195 psi
1.130" 27,521 psi
1.120" 29,079 psi
1.115" 29,924 psi
1.100" 32,900 psi
1.075" 39,641 psi
1.050" 50,954 psi
1.040" 57,926 psi
1.030" 66,890 psi
1.020" 80,345 psi
1.010" 101,286 psi
1.000" 138,744 psi

Standard OAL for the .40S&W is 1.120" ... table data from "Handloading" by Charles E. Petty, American Handgunner Jan/Feb 1998, p41.

YMMV, but it is verifiably possible to KB a handgun due to the increased pressures generated by bullet setback.


I don't believe these numbers and I don't care who wrote them. Read the article, the bullet was pounded in the case all the way. Much farther back than any setback! He chambered it and fired it. No damage.
Semi Wadcutters set into the case deeper than round nose. Does the pressure double? According to these numbers just that little bit they would.
I don't buy the pressure quadrupaling going from 1.20 to 1.00" OAL.

I know, I probably spelled quadrupaling wrong!

jim8115
November 22, 2013, 11:44 AM
I don't believe these numbers and I don't care who wrote them. Read the article, the bullet was pounded in the case all the way. Much farther back than any setback! He chambered it and fired it. No damage.
Semi Wadcutters set into the case deeper than round nose. Does the pressure double? According to these numbers just that little bit they would.
I don't buy the pressure quadrupaling going from 1.20 to 1.00" OAL.

I know, I probably spelled quadrupaling wrong!
Yea, I often wonder about those numbers. I know in my XD, if I want to run SWC's, I have to seat them at 1.085. I only had to adjust the powder .2 grain to achieve the same velocity that I get at 1.120

MarshallDodge
November 22, 2013, 12:22 PM
sexybeast- Before you throw the baby out with the bathwater, that test in the article was written based on a certain powder and bullet. Not all conditions are identical.

A faster powder will spike dramatically when bullet setback is encountered.

sexybeast
November 22, 2013, 12:32 PM
Those numbers! Yeah I will throw them out with the baby and the bathtub and the bathwater.
2/10 of an inch decrease in OAL will result in four times the pressure? No way!
What powder were they using? Titegroup or Bullseye won't do that.
More internet hype about how terrible the 40s&w is. Especially if its a Glock!
Don't believe it.

SDGlock23
November 22, 2013, 03:57 PM
Yeah I have to agree, those numbers are bogus, probably supported by the same people who think 180gr is too heavy for the .40, a bunch of know-nothings.

Barr
December 24, 2013, 12:28 AM
An unmentioned possibility is tumbling media left inside case, this can also take up volume. This is a much more common problem in .38 Special or .357 Magnum. A powder check die is a very good idea.

HisStigness
December 24, 2013, 12:47 AM
Glad your buddy made it out with all his fingers! Now I'm worried about bullet set back from reading this thread. Does the bullet seating die in my Lee carbide 3 die set apply tension to the neck? Do I need to go out and buy a crimp die now?

TroyUT
December 24, 2013, 08:29 PM
I'm going to throw my two cents in here as well. I recently had a double charge in 9mm with I Glock 19. Luckily I escaped serious injury and the weapon was not badly damaged either. Now the remains of the case in the OP pictures looked exactly like the case from my incident. I even pulled my remaining rounds and found another double charge so I know for a fact that's what happened. I since changed my practices and powder and I now reload safer. If I saw that picture and had to guess what happened, I'd be certain it was a double charge. Good job that his friend recognized the unsafe reloading practice and made the necessary changes as well. I will be honest it was scary for me reloading again after it happened but after I successfully loaded a few batches of rounds and shot them the fear subsided.

sexybeast
December 24, 2013, 09:45 PM
TroyUT, What kind of press do you use. Just curious?

TroyUT
December 25, 2013, 12:19 AM
I use a Lee Classic Turret. I just recently (within the last couple months) started reloading and was using HS6 which allowed me to double charge a round without coming over the top of the case. I was not being thorough and checking each case for the correct charge visually before seating the bullet. Long story short , I learned to visually check each case before seating and I now use Unique as well.

sexybeast
December 25, 2013, 12:32 AM
I started on a Lee Turret press. Mine self indexed. Are you manually indexing?
I use quite a few powders that will easly fit and make a double charge. If your press self indexes it "should" not be a problem. Presses like the Dillon 550B don't self index. I know quite a few people that have blown up a gun with a 550.

TroyUT
December 25, 2013, 12:38 AM
Yeah I use it so that it self indexes however I was just cranking out rounds at light speed without a care in the world not thinking that I should actually be paying attention to what I was doing like everyone else recommends.:cool: However that was definitely an eye opener forme to slow down and focus.

sexybeast
December 25, 2013, 12:48 AM
"Light speed" and "reloading" don't do well together. Especially with a turret press.
Sounds like you will have a progressive in your future.

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