Kaboom :-\ . 223 pics and video

[Tracy]

Looks like OOB to me. OOB would likely still drive the bullet out of the barrel and perhaps hit the backstop. And it wouldn't be driving the bcg back with 50K pressure because unsupported brass won't allow that much pressure to build.
The type of damage I'm seeing is completely consistent with out of battery ignition.

[runfiverun]

initially I thought OOB too.
but the bolt head has to rotate and come back into place for the firing pin to reach the primer.
that plus the brass around the mouth of the chamber.
the AR is pulling the case out of the chamber while the case is still under pressure, which would allow the case head blow out.
the projectile velocity could have been very slow while the bolt speed would be very high, even without the gas volume to push it rearward.

[M-Tecs]

In the video the you can't tell if you ejected brass when you manually cycled it but I would bet you did.

I am far from an expert on blown AR's but I have inspected and or repaired 9 or 10 that had blown. In addition to building ar service and match rifles I managed a machine shop and a nondestruction inspection shop. A couple of shops brought me stuff to inspect

One coworker blew two ar's on one prairie dog trip. He had just started using a Dillon swager and was collapsing the primer pockets so he had primers above flush and had slam fires. Only non-repairable damage was to the bolt. One was cause unkown but all the others happened after a stoppage and manually cycling a round.

Damage looked exactly like yours except the one cause unkown. That one was much more severe. Over the chamber 1/2 the barrel was blown off.

All the others had a bullet in the bore due to various reasons. Mostly no powder in the case but one was a long seated bullets. The bolt didn't close and shooter ejected the round racked another in and fired. In addition to loose powder in the action an unfired primed case was picked up.

Bolt carriers, bolts, cases and uppers failed just like yours.

As stated above oob is not possible from the hammer hitting the firing pin due to the design. OOB firings can be caused by high primers, broken firing pins or something acting as a firing pin. Out of tolerance part can also do it but I have yet to see or hear of parts that far out of spec.

Other than a life or death situations all malfunctions need to be inspected before chambering another round.

[M-Tecs]

On a side note I was out at the range and a shooter was having lots of failure to cycle/issue. I normally don't stick my nose into other people's business unless asked. I was testing a couple of match ar's

This shooter came over and asked for help. These were his first reloads since started turning necks. He did 100% cleanup on the necks and was using standard dies. The bullets would push into the case when chambered. I don't remember his load specifics but I do remember he was using TAC. Even with the bullets pushing in primers looked ok.

[M-Tecs]

I guess its why smart simple folks prefer a good bolt action.

Uncalled for and baseless.

[Three44s]

It strikes that the OP had two slugs traversing the barrel at once.

Glad he's alright!

Three 44s

[earlmck]

There is another possibility and I might even put it as a probability: your case was too long -- needed trimming. A too-long case that jams a bit into the leade and doesn't release the bullet easily can create amazingly high pressure. (yep, voice of experience here).

I just got done trimming a whole bushel of 223's because after just 4 (maybe 5) reloads one of my cases had grown so much that it stuck the case a bit in the chamber and fortunately didn't allow the bolt to close, so wouldn't fire. Most of my cases were still in spec but I had a few that were definitely too long. (Yeah, mixed range pick-up brass). I am old enough to know better -- kicking myself for not checking brass length earlier but sure glad that baby didn't fire or my rifle might have looked like yours.

[jonp]

"One coworker blew two ar's on one prairie dog trip. He had just started using a Dillon swager and was collapsing the primer pockets so he had primers above flush and had slam fires"

Loose primer pocket causing the primer to back out and a slam fire on the reloads?

[Lloyd Smale]

few things could cause it. Sometimes a bit of powder bridge in a measure and can drop with the next charge and yes you can overload a 223 with 335. Second is a squib but you would have know that because you would either have heard a primer go off or at least had to pull the charge handle a second time. My best guess is your gun fired without a round fully into the chamber. Either caused by brass that didn't size down enough or brass to long. I haven't seen an AR do it but ive seen a couple glocks go kaboom because of it. Another thing could be tired brass. If your brass was getting a bit old and stretched you could have had a case head separation. But that would probably not show flattened primers. Ive come to only use ammo in my ars that have been small base sized and trimmed after each firing and have had the primer pockets swaged. Guarantees they go in the chamber all the way reliably and wont slam fire due to a primer not being fully seated. Ive got a Dillon trimmer and swagger so it isn't much more work to guarantee reliability. I also have an led light mounted on my press over the powder drop station so that if a measure does bridge and drop to much its easy to see. ALLWAYS visually look at each round so that you notice any major difference in powder level in the case.

[M-Tecs]

"One coworker blew two ar's on one prairie dog trip. He had just started using a Dillon swager and was collapsing the primer pockets so he had primers above flush and had slam fires"

Loose primer pocket causing the primer to back out and a slam fire on the reloads?

No with the Dillon swager if you adjust the swager too deep you push material into the bottom of the primer pocket. This seems to only be an issue with 223 due to the small size of the internal support rod.

[M-Tecs]

For the folks that believe you can fire an ar out of battery take a primed case and try it. The bolt has to be fully rotated before the firing pin can reach the primer.

The video clearly shows and the OP stated he manual cycled the next round after an ftf. The bolt carrier was blown. That happens from massive over pressure.

In the early day of AR in highpower comp. AMU used a load that called "V8" for long range. The had to use LC prime and crimped brass. Brass was shot after one firing. Pressure was over 70,000 psi.

[bob208]

shooter error when shooting if the gun goes poof instead of bang stop and check the bore. do not load and fire another round and fire. you had a stuck bullet in the barrel.

[rockrat]

If not an OOB, then to me, the only other idea would be two bullets going down the bore. Pressure in the system was who knows how high and when the two bullets passed the gas port and the bolt started unlocking, the pressure was still so high that the case head was essentially sheared off when it became unsupported and the high pressure deposited the brass at the back of the chamber. So, a squib, followed by a normal round

[vzerone]

I see M-Tec is savy of the fire out of battery myth! Just not going to happen with an AR. The reason the carrier blew is due to escaped high pressure gas entering it. There isn't any firing pressure on a carrier. A carrier is just that..a carrier....it carries the bolt. Now when the rifle is functioning there is some stress on the cam bolt which the carrier is part of. Take a primed case (no powder no bullet please) place it in the chamber and let the bolt slam shut on it. See how many times you can do that. I'll bet till you get tired of doing it. That slam fire story about the firing pin causing it is a myth. Now a high primer might just do it. The primer in that case head just doesn't show massive pressure. I still feel the case let go. Try another test. Prime a case and load a bullet WITHOUT any powder and just see if the primer drives the bullet out of the case and how far. An AR bolt/carrier group just does not have enough oomph to chamber a cartridge if there is a bullet in the throat that the new rounds bullet may touch, unless you have no neck tension at all on your loaded round. Cardinal rule: Whenever a round doesn't fire ALWAY check your firearm especially the bore to make sure there's not a bullet stuck in it.

[JonB_in_Glencoe]

H335 is a Hodgdon powder, obviously. The Hodgdon reloading site shows 3 different 55 bullets for 223, none of which are 55 FMJ designs. The OPs load of 24 grains exceeds max for 2 of these 3 bullets.

>>>SNIP

That's interesting, I don't doubt you, but I recall it being more, as I've used H335.

I dug into a few manuals.
Lyman 49th Has 27gr as Max for the only 55gr jacketed bullet listed.
Nick Harvey's manual also lists 27gr as MAX.
Hodgdon paper manual lists only one 55gr jacketed bullet and Max was 25.3gr.

[Larry Gibson]

Did not fire out of battery or bolt and bolt carrier would have been blown to the rear.

OP had a bore obstruction. Watch the sequence of events in the video. OP pulled the trigger, just a click, no bang, no recoil. OP Ejected the case and next round....Ka-boomed..... the bullet from the previous FTF round that was cleared probably had no powder and the primer drove the bullet into the leade where it stuck. Next chambered round had it's bullet pushed back into the case when it was chambered. Obviously 23 gr H335 is a gross overload for 110 gr of bullet in a .223.

Any time you have a misfire (FTF) like that, in a match or not, and you can't tell if the ejected case still has the bullet in it you should stop and check the bore. Yes, you will lose the match but better that than lose the rifle and perhaps some part of yourself........

The RO should have stopped the OP on the misfire. Numerous 3 gun matches I'm aware of have included mandatory stopping the shooter if a FTF round can not be seen to still have a bullet in it......this example is the classic reason why........

[popper]

Just not going to happen with an AR. And when YOU have had one - OOB - , you will believe that even the design can be beat. It is NOT a myth. I agree that you MUST do a chamber check on a FTF in ANY gun.

[vzerone]

If you fire out of battery, and Mr Gibson agreed with me, that carrier/bolt group is going back and possibly driving itself, the buffer and spring, and maybe the lower receiver tube extension THROUGH your shoulder. Anytime that doesn't happen, you don't have an out of battery firing. The AR firing pin barely protrudes from the bolt face and it doesn't do so until the bolt is in full battery and fully rotated. In addition, and some of you many not know this, the leading edge of the slot in the bottom of the carrier is also designed so that if the bolt isn't in full battery it hits the hammer and prevents it from striking the firing pin.

[vzerone]

If the op had been shooting the he stated and he didn't mention anything about them being hot or extremely flat primer and swelled web area of the case I highly doubt it was a overload. Again Mr Gibson stated a H335 load with a 110 grain bullet for comparison. I'll also bet my gun safes that the op's rifle has a 5.56 NATO chamber rather then an honest 223 Remington chamber and is more forgiving with loads that are for the 223 Remington.

I highly doubt also that the his bolt is 9310 steel. It's more then likely the standard carpenter steel.

Mr Gibson and I are in the same boat on this incident.

[vzerone]

Beg your pardon Mr. Beeman, I was among the first, if not the first, to mention it wasn't an out of battery occurence back in post #18. I too am more then familiar with the mechanics of the AR. I also didn't point you out on anything, but yet you seem to think so.

Assembling an AR doesn't mean you know how they function. They really aren't a plug n play. More then likely a very high percentage of the time the rifle will function, but when it doesn't and something is the matter with it, that's where the novice gets lost.

I may take my AR 15 out of the safe and just load cartridges with no primers, that is just the bullet and live primer and fire the first one to see how far in the rifling the primer pushes the bullet. There are many things dependent on how far that bullet will go. Just to mention a couple neck tension and if there is a crimp. I'm not positive just a primer will push that bullet up the tube far enough that another cartridge will chamber. I've already mentioned we don't know how tight the op's bullets were in the neck of his reloads.

Now I've had "squib" loads in the far past, but even with earmuffs on you can hear something. I don't classify a squib load as just a primer, but one that doesn't have the full charge of powder.