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View Full Version : AR Explosion Video: What Happened?


Bubacus
March 24, 2017, 22:16
Any guesses about what caused this explosion?

<iframe width="854" height="480" src="https://www.youtube.com/embed/-KJq23shaTc" frameborder="0" allowfullscreen></iframe>

notfrommt
March 24, 2017, 22:19
Out of battery or case head failure.

It's why I don't use plastic magazines. This event turns them to shrapnel.

Tuscan Raider
March 24, 2017, 22:25
On top of the idiot behind the gun,
squib, re chamber, kablooey.

garandguy10
March 24, 2017, 22:33
If you could get a close up of the ejected round, iI suspect you would find that there is no bullet in it, bullet probably stuck in barrel.

notfrommt
March 24, 2017, 22:47
Who brings a knife to a gunfight? Look closely. I guess he was at a range in a real bad neighborhood.

gentlemanjoe
March 24, 2017, 22:50
If you could get a close up of the ejected round, iI suspect you would find that there is no bullet in it, bullet probably stuck in barrel.

Yep. Squib:cry:

DJ
March 25, 2017, 06:49
Yes sir that would be my guess. He charges the rifle, pulls the trigger and nothing. He works the action and kablooey.
Squib.

W.E.G.
March 25, 2017, 07:48
I saw a sectioned AR barrel that was bulged, and had THREE bullets stuck in the barrel aft of the bulge.

http://i227.photobucket.com/albums/dd7/rkba2da/memes/B6402C0A-781D-404A-8667-4097CF7389BF_zpsafaeef2j.jpg

meltblown
March 25, 2017, 07:50
Big dumb fugger manhandling his rifle and not paying attention to what's going on.

TenTea
March 25, 2017, 09:37
Big dumb fugger manhandling his rifle and not paying attention to what's going on.

At least it was captured on video and saved for all posterity.

[slick] Teachable Moment [/willie]

hardass
March 25, 2017, 12:05
If you go to settings and slow down the video you can see the ejected rd hit the box and table. It looks like the projectile is still in the case.

I also captured a still and enlarged it. It's fuzzy, but looks like an unfired rd.

raubvogel
March 25, 2017, 12:38
According to http://www.calguns.net/calgunforum/showthread.php?t=1311756, no obstructions.

Fn/form
March 25, 2017, 17:49
Sounds like the rifle lived up to its name.

I'd take a close look at that remaining lot of ammo for sure. Each loaded case weighed, each loaded neck mic'd/gaged.

ETA: looks like the bolt was sticky on the ejected round before the kaboom.

ByronF
March 25, 2017, 19:04
Do I understand that a half charge could light all at once and cause a YUGE pressure spike? If so a half charge is way more likely than an overcharge. One reason I like 4895 for 5.56 is I can pretty much fill to the mouth and stuff on a bullet and be OK. Maybe not precision without weighing, and some variation in case volume, but no way I'd blow up a rifle even without a scale. I ALWAYS. visually inspect my loading block of cases after throwing charges. If one looks even a little low I throw a new charge. And I weigh every tenth charge to make sure my scale is throwing consistently. My RCBS. theower didnt come with a baffle in the bottom but I added one and consider it mandatory. Powder in the reservoir settles and after several throws becomes denser. The baffle keeps density at the drum constant, but I still throw a dozen charges before I start filling cases.

MistWolf
March 27, 2017, 00:22
The manager of the range who posted the original video stated there were no squib rounds. All the rounds the shooter ejected were intact. There were no obstructions left in the barrel from the day before

hueyville
March 27, 2017, 08:02
Do I understand that a half charge could light all at once and cause a YUGE pressure spike? If so a half charge is way more likely than an overcharge. One reason I like 4895 for 5.56 is I can pretty much fill to the mouth and stuff on a bullet and be OK. Maybe not precision without weighing, and some variation in case volume, but no way I'd blow up a rifle even without a scale. I ALWAYS. visually inspect my loading block of cases after throwing charges. If one looks even a little low I throw a new charge. And I weigh every tenth charge to make sure my scale is throwing consistently. My RCBS. theower didnt come with a baffle in the bottom but I added one and consider it mandatory. Powder in the reservoir settles and after several throws becomes denser. The baffle keeps density at the drum constant, but I still throw a dozen charges before I start filling cases.

Have half different loads for pistol and rifle developed that dip case in powder, shake off till level with case mouth and stuff bullet on top. Was done as part of an experiment to see how little equipment was absolutely necessary to load ammo in a survival scenario. A Lee Hand Press or Lee Loader with a two cavity aluminum bullet mold can keep you running if have powder and primers. With a 45-70 lever action can make black powder, cast bullets and primers are only component needed with Lee Loader/Hand Press setup. Of course one of their dippers doesn't add much to a kit if want to use fast powder and get more rounds per pound.

TenTea
March 27, 2017, 08:43
Sounds like the rifle lived up to its name.



A gernade blowing shrapnel into the expanse?

http://lowres-picturecabinet.com.s3-eu-west-1.amazonaws.com/162/main/2/743729.jpg

2barearms
March 27, 2017, 09:18
Case Head separation. The ammo is Federal American Eagle...aka crap. The case failed in the chamber with the bolt locked.

Note: Not specifically related to this incident: this is why I only make rifle ammo from once fire military brass in military calibers. If you reload range pickup brass you have no idea how many times its been through a press.

hueyville
March 27, 2017, 17:38
Read entire post mortem, bolt split following case head separation feeding gas back into upper receiver. My guess is in front of a Kali"fornication" civil court judge and jury this case is a gold mine littered with diamonds with entrance blocked by truck load of 10 karat flawless emeralds. Colt factory rifle explodes using factory loaded ammo. Been leary of the Colt Expanse line since first saw. Comes with plug where forward assist goes, no dust cover door or rear sight. All that has to be added. If cut corners like installing a plug in upper rather than sticking a $5 forward assist assembly how deeply did they cut quality of parts throughout entire rifle?

For a rental range to buy cheapest Colt ever made for a range whore seems sketchy also. If shooter wants to cash in on the Powerball lottery without buying a ticket he has it laid out on film with good chain of evidence that first year law student could litigate. Why I purchased five W.O.A. 6.8 bolts to go into the $59 Palmetto mystery BCG's. Also why use Superbolts in the 6.8's that hammer on the hardest. Also why any mystery steel non HPT/MPI bolt purchased in deal becomes an end of world spare. Had not had an upgraded bolt in AR I KaBoomed would have had to extract BCG from my skull.

OMR_RDTandE
March 27, 2017, 18:35
Do I understand that a half charge could light all at once and cause a YUGE pressure spike? If so a half charge is way more likely than an overcharge.

That is my understanding, also. The charge will detonate, rather than burn. Saw a similar aftermath in an AR-15 back in '94.

MistWolf
March 28, 2017, 11:55
The whole "light charge detonation" thing has been speculated about since I can remember. No one has ever been able to document replicating it

2barearms
March 28, 2017, 13:11
The whole "light charge detonation" thing has been speculated about since I can remember. No one has ever been able to document replicating it

Thank you. The interesting part is that every time
the subject of subsonic load development comes
up so does the nonsense about the " secondary
explosive effect" I would never suggest that
it can't happen.

It very much like the knuckle heads on one of the alternative
energy boards I was on years ago. The moment
you mention that you are working with steam
they go full retard no matter how you plan to
use it.

notfrommt
March 28, 2017, 15:21
According to http://www.calguns.net/calgunforum/showthread.php?t=1311756, no obstructions.

Thanks for posting this link. IMO this was caused by a soft headed part. As evidence of this is the image of the head of the casing in the bolt with the primer and material below the primer missing in the direction of the feed ramps. Proof of this would be to measure hardness in the head fragment (easy to do).

As an aside, the rifle did a fine job of directing errant energy away from the shooter. Uncomfortable; yes. Deadly; no. Another reason to never stand next to the gun someone is shooting.

hueyville
March 29, 2017, 11:32
Out of battery or case head failure.

It's why I don't use plastic magazines. This event turns them to shrapnel.

I don't like plastic magazines either, when had my AR KaBoom was one of the few times was using a Pmag. Another thing do to alost all builds now is add these Israeli FAB mag well grips/mag funnel. If using stock collapsed inside a structure gives a good grip, makes reloading under stress easier with big funnel to hit and adds more protection if lower explodes when rounds in magazine start cooking off.

http://i63.tinypic.com/2z88028.jpg

http://i68.tinypic.com/xmpjl3.jpg

http://i64.tinypic.com/23u1nb9.jpg

http://i67.tinypic.com/2e3od9x.jpg

Not affiliated with these folks nor was I really wanting such a product but a friend wanted a vertical grip on an upper I built and ordered one of these to see if he liked instead. I liked so much put on a SlideFire AR then started adding to more and more builds. Now any lower that will accept it gets one. Protects lower from getting beat around in truck also. The ergonomics and multifunction use makes it one of the best inexpensive accessories have found. Usually order three nlack, three green and three FDE per order then when run low restock based on colors have in stock. Prefer the new models that have the serial number window but the older ones without can be found cheap.

Augdog
March 29, 2017, 18:01
Case Head separation. The ammo is Federal American Eagle...aka crap. The case failed in the chamber with the bolt locked.


I call BS on case head separation, seen numerous AR15 case head separations come through the gunsmith and nothing like this, most of the time we just pull the case remains and clean the chamber and the gun is back up and running. Why did the gun malfunction and have 2 fail to fire to begin with? Not because of a future case head separation, most likely a squib that was forced further down the barrel with each new round until the bolt could go into full battery - Kaboom so bad it cracked the bolt in half.

MistWolf
March 30, 2017, 12:49
...these Israeli FAB mag well grips/mag funnel...adds more protection if lower explodes when rounds in magazine start cooking off

As I've said before- Hueyville is a strange place to live :D

most likely a squib
The manager of the range who posted the original video stated there were no squib rounds. All the rounds the shooter ejected were intact. There were no obstructions left in the barrel from the day before

hueyville
March 31, 2017, 18:54
...these Israeli FAB mag well grips/mag funnel...adds more protection if lower explodes*when rounds in magazine start cooking off

As I've said before- Hueyville is a strange place to live :D

http://i61.tinypic.com/2vws1i1.jpg

Only thing resembling an injury happened when top rounds in magazine cooked off inside a Pmag and the lower KaBoomed also. Not my greatest day but didn't hide from it. One of those deals still not 100% sure of actual cause due to several different possibilities.

http://i60.tinypic.com/26426c8.jpg

http://i57.tinypic.com/15yfy48.jpg

http://i58.tinypic.com/260plkg.jpg

One thing is sure, a burly bolt that stayed locked up likely saved any real end user injury but can see busted Pmag and bullets strewn somewhere have pics of the cases that cooked off in the magazine. So yes, if can add some meat around that area I do so these days. Had to extract a piece of busted magnesium lower from base of left thumb. Entire upper and lower turned into a freaking bomb.

Most insist it was a squib followed by a full charge which was not the case. Was doing initial sight in at 25 yards with scope set at 7x. Was seeing every bullet hit target and twisting knobs to push scope closer to where wanted rounds to land. Did every post mortem could do, pulled down all 100 rounds from box and every charge was dead solid perfect. What was wrong had poured a bag of 62 grain "pull downs" from major component vendor whom have used for years buying tens of thousands of pull downs with no issue. Turned out bag of bullets poured from had mix of 62 and 69 grain bullets plus a few 6mm bullets just to spice it up. Was using a Dillon 550b with a very old first generation second party bullet feeder. Discovered that either by design or due to wear the feeder would send the 6mm projectiles through the device and drop them neatly on top of case where belling die in powder measure allowed them to sit long enough for seating die to mash it on home. I believe the 6mm bullet extruding down a 5.56 mm bore allowed the case to rupture, setting off top round in magazine and all went to hell from there. Saw hole appear in target clearly on round before KaBoom reached up, twisted the knobs and squeezed off the next one and Boom.

Barrel wasn't bulged anywhere and the bullet hit paper in pieces. Nice line of holes walking toward center then raged hole with some small rips/tears from bits of jacket/bullet core. Put new extension on, rebuilt all parts except magazine, BCG, upper and lower into a new rifle the next day and that barrel shoots 5/8" MOA with good ammo to this day. Even reused gas tube. My opinion is a 6mm bullet was not noticed (better post loading inspection done now) forced in case till hit lands of rifling and that's when pressure started blowing case to pieces and vented gas down into magazine blowing up top round. 40+ years and over a million rounds of no issue reloading down the tubes. Vendor now states on all pull downs end user responsible to measure and weigh each projectile as mix ups happen in there bullet separation process. I still use them but only for green tip pull downs and other designs easy to spot a mismatched projectile.

Hueyville was a strange place that day. Retwisting parts into new rifle next day had the wife in a tizzy till proved they would hold together.

MistWolf
April 02, 2017, 14:31
I have never heard of rounds cooking off in a mag from a ka-boom, before.

I remember now, that you had an AR explode and I'm happy that you escaped with only a minor injury. I remember you talked about successfully reusing the salvageable parts.

P.O. Ackley did an experiment where he fired .323 (8mm) diameter bullets through a .308 bore. He took an 03-A3 and reamed just the neck portion of the chamber to accept the .323 bullets. He then loaded 8mm bullets in 30-06 cases and fired them through the modified chamber. He found no signs of unusual pressure from swaging bullets down the tighter .308 barrel. What he did find that cause a catastrophic pressure event was trying to fire the .323 bullets in a chamber with the neck diameter to fit .308 bullets. He stated that the tight neck kept the bullet from moving as it should as the powder burned and pressure built. Going with your theory of accidentally loading a 6mm bullet in a 5.56 case, it was the tight fit in the neck that caused your AR to explode.

Yes, I still think Hueyville is a strange place to live, but it has a charm all it's own. I admire that you do things, even when your wall of text and typos conspire to make reading your posts about those doings nigh unto impossible to decipher for this simple old wolf.

Don't worry too much about how strange Hueyville seems to me. I suspect that life in Wolf Hollow has it's share of weirdness, too

hueyville
April 02, 2017, 18:12
And why I still say not 100% sure of cause, know wasn't a squib and your theory that case blew due to tight neck impeding bullet movement long enough to rupture case is as good as any. Everything I did in post mortem kept bringing me back to those 6mm bullets and fact the bullet feeder would seat them. Also was using CFE 223 which many have noted odd pressure spikes with, especially at gas port. One guy ran a test where was getting in spec chamber pressure with CFE 223 but port pressure was 30 to 40 percent higher than other powders with similar chamber pressure. Don't remember how he was measuring each but could find the article in my archives if looked long enough.

Not mine but told top round in magazine cooked off in this AR Kaboom. Guy mixed pistol and rifle powder for some reason.

http://www.thefirearmblog.com/blog/wp-content/uploads/2011/04/img00129_20101226_1008-tfb.jpg

A buddy that Kaboomed multiple guns with sloppy reloading habits and alcohol involvement at bench had a 1911 squibb, kaboom then secondary kaboom when top round in magazine cooked off. Oddest part was he still had two had hold on pistol and the wooden factory grips were both gone. Extruded them between his fingers or the were transported into another dimension. Read about a similar incident.

Disclaimer - I'm not faulting the pistol for this issue, my suspicion is a week case...but I'm hoping some of you fine folks can either confirm or offer up other possibilities.

The 'facts'....the load used was a .45 acp, loaded with 4.7grn of titegroup and used a hornady 230 grn FMJ-FP at 1.200" with a winchester primer. The big unknown here is the age of the case used, it was possibly range brass i'd picked up earlier and reloaded.

The loads were a bit snappier than my other loads and had a tendency to not always feed properly...at this point I should have stopped. What happened was that I was shooting at bowling pins and felt a boom...kaboom kaboom...and then all was quiet and my hand was slightly achy and my nose was bleeding.

The round in the chamber ruptured and caused the cooking off of the 2 rounds in the magazine. The magazine was blown out approx 5 feet and is now jammed as the internals are a bit bent up. The slide is cracked and bent slightly, the extractor is jammed into the slide further, my lovely Esmeralda grips are cracked...the barrel however appears to be a-ok.

The good news is that I didn't lose any fingers, bits of my hand or go blind...but what I do know is that I have 2 small itsy bitsy pieces of metal in my nose, and one in my forehead (getting them looked at on friday)

See link for pictures:

http://forum.m1911.org/showthread.php?68840-Ruptured-Case-kaboom

Have seen wheel guns kaboom and blow up rounds in adjoining chambers.

http://www.gunslot.com/files/gunslot/images/64858.jpg

http://i1136.photobucket.com/albums/n489/kcq1/nCpTz.jpg

Rather than string on with more pictures just put revolver kaboom in Google task bar, click images and will see dozens of KaBoom's cooking off rounds in adjacent cylinders. One of the most impressive is a Colt Anaconda. Back in the 70's when wheel guns were king saw hundreds of them blown up, usually a double or triple charge of Bullseye.

My no passed on good friend with the drinking and poor mechanical comprehension issue (couldn't even jump start a car) did all kinds of stupid stuff. One evening (lived with me and my parents several years to avoid his home life) he wentered to my bench to assemble some of my 38 special 140 grain wadcutters using 3.1 grains of Bullseye. One load used the stuff for as was cheap and could drive tacks. He loaded 100 rounds, every other no powder, every other double charge. Was shooting a Model 27 with countersunk chambers for case heads. He squibbed a round then sent a heater behind it clearing the stuck squibb. Was pretty funny so he assumed single mistake then pop followed by another heater and next two did same. Examined the big 27 and it didn't even notice 6.2 grains of Bullseye pushing two 140 grain wadcutters. I normally shot 200 grain cast SWC with huge charge of unique with it so we ran entire box just to save pulling down all his mistakes AGAIN. What was a hoot was when had two squibs in a row followed by a double charge pushing three bullets out the bore. Why I say the Smith M27 is likely the toughest handgun ever made.

Have a folder at work with possibly over 1,000 kaboom pics. Majority are wheelguns but Gen 1 and Gen 2 Glock's are catching up as people buy police surplus pistols on the cheap, don't have them checked out then run really hot loads in the unsupported chambers. Glock got that worked out by end of Gen 2's. AR's are coming on strong in the frequency of occurrence. Seen every type gun made blown up from derringers all the way to modern field artillery pieces. We humans can screw anything up. It's the ones that learn from mistakes that tend to live longer.

Can't count the number of loads have tested with gun in a rest and pull trigger with a string. Have a 44 special load using a cast gas check Keith bullet for bear defence when in Wind Rivers, Tetons, Bear Tooth, etc. Kept pouring powder to cases and firing in a 44 magnum Redhawk till started blowing primers. Backed off to highest load that didn't blow them but flattened them and swelled primer pocket so much could not seat new primers as would fall out and stretched web/case head till ejection took a rubber mallet. Once found edge of 44 special case ability to stay together in the big Redhawk put five in my lightest five shot 44 special in a Ransom Rest and ran five through pulling trigger with a string. Measured cylinder holes before and after, didn't stretch the pistol and that became my "stick pistol in bears mouth as chews off hand and yank trigger five times" while praying that gun does blow up and kills bear in process.

Sometime Wolf Hollow and Hueyville may converge in a space warp and sure something odd will result.