OP for what you spent on that rifle you can build a very nice rifle in today's market.

Yep.  OP, very sorry to hear what happened, but I'm glad your boy is ok.

There's not much recourse, Norinco isn't going to help you out.  It's a tough lesson unfortunately.

IMO, the Carbon-15 was never good.

You can build a much nicer rifle for the same or less money these days.

Glad your boy is ok. Replace it with a Colt 6920 and feed it better ammo.

Interesting that the ammo in the pics is in a red box... I too remember it being In a yellow box.

Glad your son is okay.

Were you floating down a river? Cause that's how we blow that model up on arfcom.

Sorry about what happened.  What a lousy introduction to the AR world.  However, other than somebody else's reloads, you probably couldn't have had a worse ammunition/rifle combination (don't get me wrong, the case failing like that would have messed up a conventional aluminum AR, but it wouldn't have been as dramatic).

The good news is that ARs and ammunition have never been less expensive than they are right now.  If you just want to shoot on the cheap, get something by Palmetto State Armory.  If you're willing to spend upward of $1k like you did on the Carbon 15, get a Colt.  Federal XM193 or XM855 is good, inexpensive plinking ammunition.

IMHO that's the problem with trying to mimic the dimensions of AR's in material that's not aluminum or of equal or close material properties.

The carbon 15 would probably have been OK if they had beefed it up a lot to make up the material property differences, just like 3d printed receivers.

But, that would kill all the weight "savings".

Experience is what you get.... when you don't get what you want...…

You got plenty..

Junk gun.... with bad ammo.... recipe for this...

Glad the boy's ok, OP.  Looks like you've got enough of the lower left over to run an AR-57 upper, if Bushmaster doesn't want to warranty it.  If you go that route, throw a thumbhole stock on it to reinforce the lower.

Here's a couple of threads to help you out:

https://www.ar15.com/forums/t_1_5/2219868_-300-AR-thread-for-summer-Post-pics-of-your-cheap-ARs-.html

https://www.ar15.com/forums/t_1_5/2146304_That-Every-Man-Be-Armed-Free-AR-parts-Please-contribute-Trash-Panda-16A-complete-pg-33.html

The good news is you don't even need to spend $300 to build a new rifle - your bbl & the rest of the upper are good, minus the actual upper.  Looks like the optic survived as well.

You'll need a new lower to run standard mags, but you should be able to move your hammer, trigger, & safety over to the new lower, along w/ the buffer tube & stock.  Looks like everything on the BCG survived other than the extractor.  Clean it well & lube it after you replace the extractor, and see if the firing pin suffered any erosion - don't want to punch through a primer on your next shot.

While early Carbon-15s had proprietary parts - I'm still running a Carbon-15 bbl on a .22 LR rig - Bushmaster standardized the design to run ordinary AR-15 parts, so other than the receivers you trashed, you can move almost everything over to new receivers and go back to shooting.  Looks like you're out less than $100 before shipping, and you'll need an AR armorer's wrench.

Upper:  https://www.primaryarms.com/radical-firearms-ar-15-stripped-upper-receiver-forged

Lower:  https://www.primaryarms.com/anderson-manufacturing-ar-15-stripped-lower-receiver

And Bob's yer uncle.

Addressing the stupidity in this thread:

1) Carbon 15s are not known to be "explody".  A few have been known to crack where the barrel meets the upper but kabooms in ARs are catastrophic failures either with the ammo, bolt, or extension.  From the pics, it's obviously the ammo.
2) Weibull curve is not at play as at 1k rounds, you are actually in the safe zone for ARs
3) Poster recommends a radical firearms AR which are known to have extensions work loose, after OP experiences a KB?

You can rebuild it, it is not really that hard to do. Good luck.

My thoughts were similar to backbencher's. There is a lot that cam be salvaged of what remains, the carbon receivers being fragile took the brunt of the force leaving most of the metal components intact. Have everything inspected by a competent gunsmith. At a minimum upper and lower receivers and extractor, possibly a bolt. Like was stated $100-$150 and you could be shooting again with a rifle you could trust.

Another recommendation for PSA. I just put together a really nice AR with Magpul furniture and a polished trigger for less than $430.

They have a special now, a kit without the stripped lower for $259. Add a $30 lower and you're under $300. For a complete AR. For what you spent on that Carbon, you can get three ARs and with money left over for a dozen mags.

These are the salad days for buying ARs. Belly up to the buffet, my friend.

I blew up a carbon 15 with  a 9mm Uzi mag adaptor in it. I’m pretty sure it was a squib round stuck in the barrel.  I was able to beat the (steel) Uzi mag adaptor into usable shape but the carbon 15 lower was toast.

I only use factory fresh ammo now, learned my lesson.

That's surprising it actually blew up.  Does your adapter take actual Uzi mags?  Would you entertain an offer?

I had two of the carbon 15 pistols crack where the buffer tube screws in. After the second I had them replace it with a M4a3.

Take a look and the brass head. Post a pic or tell us what the brass is marked. If I remember right it should be CJ then a year. I am wondering if this ammo was slipped over the Northern border. Canada still imports it.

Can you post a pic of the head stamp of the live ammo you still have. All together in one pic?

This. A polymer upper or lower will split or crack but an explosion is either bad ammo or it fired out of battery.
The chamber & bolt are containing all the fury. Being surplus ammo and a novice shooter I would not rule out a squib round either.

As for a replacement, nothing wrong with Armalite but I think a good entry level recommendation would serve better. Mine would be Palmetto State Armory or Anderson.

might be a chrome lined barrel if Bushmaster used the same parts as the rest of their line up...  you are probably not into the DIY self market, but you can probably trade the remains to a buddy for something.  Somewhere between $100 and $200.

Edit: I missed the link to the gallery.

Glad you and your son are ok!

I’m so glad I decided against a Bushmaster back in 2012 when everyone was forking over $1,000-$1,200 for one..

If you want a good rifle that won’t blow up on you, but you don’t have to have the best of the best, get a PSA. They are great, and they stand behind their product.

Just out of curiosity, what markings are on the casings? I’m almost willing to bet that a LGS that’s shady enough to sell old ammo is also shady enough to pass off handloads as factory ammo.

Yeah. A coworker bought one for a grand also right after Sandy Hook. I told him to wait. He had to have it "Right now"

man i can imagine how it blew up looking at the parts. before you even have time to react you realize you are just holding onto a pistol grip with scary smoke and a pop. its ok, even good new ammo are known to be a rifle killer, just stay tuned on arfcom and people will post any bad ammo, and the hive can start figuring out if it was a one-off thing or a pattern.

pics for those that wanna see Click To View Spoiler

Damn glad everyone is ok!  OP check out Palmetto State Armory if you want to get an inexpensive AR or depending how much you want to spend on a higher quality rifle.  If you are willing to drop the coin I would suggest something like a Colt 6920 or 6720, BCM, or Spikes Tactical rifle.

The carbon guns were the problem the standard Bushmaster guns were fine. It would have served you well.

Middle picture shows extruded brass into ejector.  That is an overpressure event, or excessively soft defective brass.  Plastic construction of reciever set has nothing to do with that.  That's ammo related.

I'd still be upset about paying $1,200 for a rifle that's now considered a $500-$600 rifle. Granted, I would have been SOL if all of the NATO forces came in and tried taking our guns like everyone was sure they would (a huge reason for the buying frenzy) haha just glad a held off until prices bottomed out. Although I did pay $16 for a 50 round box of 22lr.

That’s the whole AR market. Anything you bought then is significantly cheaper now.

So you shot a plastic gun with shitty ammo and it blew up?  Huh Glad no serious injuries

 This particular old ammo was bad b/c it was bad when it was new, hence it was cheap, hence OP bought it.  That's not shady, just shitty brass.  Plenty of old ammo is quite decent, and sometimes the only way to buy a particular caliber.

I'm a little more that 60,000 rounds in on the Norinco (China Sport) 223 ammo in my gun and have never had one problem. That's why I wanted to see a pic of the head stamps to see if it was reloads. People talk shit about the Norinco 223 all the time, that's good...more for me.

Glad you guys are ok OP. The good news is, for the price you paid for that carbon15 back in the dark days, you could get a pretty premium platform for the same amount or a bit more, that will last a life time. I highly recommend doing some window shopping online and looking into Colt 6920, BCM, LWRCI etc. As others have stated, Palmetto State Armory has some great bang for buck options that should suit your needs as well.

Update guys. Bushmaster never contacted me from the email I sent Sunday so I called today. They've sent a FedEx label and want the gun back ASAP. Some posters have said I bought the ammo cause it was cheap and also said I'm a inexperienced shooter with a plastic gun and bought one cause I had to have one.

I turn 50 in a few days and have owned and shot firearms since I could pick one up and hold it somewhat straight. Not saying I'm an expert by any means and admit I had zero experience with an AR until this one. Life marriage, divorce, kids etc kept me from my first AR. Timing sucked when I finally had cash to buy one. I spent months after Sandy looking for an AR and asked many questions when this one became available. Then ammo was nonexistant after I was advised the carbon 15 was a "good gun". I looked for several months for any ammo I could find. I paid $25.00 per box of 20 Norinco because that's all I could find besides the box of Fiocchi I purchased from the same gun shop owner. He said it was a couple years old in 2013. My fault, I guess I should have researched Norinco china sport ammo back then but I trusted a licensed gun shop owner.

The AR and ammo sat in my closet until February 2019 when I decided to take my son and his friend from Germany to shoot for the first time. I hired two weapons experts ($200.00) at the indoor range to teach us about the AR so we were safe. All I can say is I wish I were shooting when it exploded so my son didn't have to live with this experience.

Thanks for all the positive responses and opinions on what happened, I've learned alot from all of you. I'll let you know what Bushmaster (now Remington) says or does after they contact me from the inspection. Some have asked for pictures of the head on unfired rounds, looks like CJ 92, pictures updated.

Looks like factory Norinco ammo to me.

No need to explain yourself.  Post-Sandy Hook was a crazy time and people were scrounging for anything and everything: rifles, ammunition of any sort, parts.  A dollar didn't go very far.  Really, it was just about the worst time to pick up an AR.  I doubt that Bushmaster will feel compelled to do much of anything as it was pretty clearly an ammunition failure and they have no control over what ammunition an end user chooses to use, but I don't suppose that it hurts to ask anyway.  Maybe they'll offer a credit toward an XM15.  While Bushmaster isn't my favorite brand, you could do worse for the money.

those posters should be given time outs really, the mods allow way too much nonsense here.  too many morons post here lately

glad you guys are ok and sounds like you may get some answers/resolution

middle fell off

I have to give credit to the guy at Bushmaster, when I called and explained what happened his first question was "did anyone get hurt"

I would talk to the gun store about the shit 30 year old ammo.

OP, my apologies.  Some here are saying it has soft brass, and one guy here says it's great.  Sorry you weren't able to snag it when it was cheap.

If Bushmaster offers you less than $300 off a complete new rifle, just build a PSA or follow the links in the $300 AR thread.  Ask for the parts back in that case.

A couple years old?lol try 21 years old at the time of you buying it. People shoot old Chinese Ammo all the time though. I’m thinking it was a rifle issue. Looks like it fired out of battery.

stay in your lane

im leaning towards that it was fired out of battery too. just by looking at the shell and how it is mushroomed out around the base leads me to believe that it wasn't all the way in.

Every AR Kaboom people say OOB.  The reality is they are wrong every time.

Every time.

Go look at the second picture where the casing was still in the chamber.  See the extrusion of the brass into the ejector?  That takes serious pressure to fluidize the brass to flow back into the ejector port like that.  Only way you can build that kind of pressure is if the chamber is locked, and it goes up into the >60,000 PSI range, to start flowing brass all the way through the head, like that, before something else gives and the pressure is released as a Kaboom.  That kind of extrusion is not happening in an OOB, which pops at much lower pressure, since that's relying on the brass alone to be holding the pressure - which it can't.

----------------
As to the root cause, it's ammo related.  Who knows, Norinco ammo is the lowest of the low.  Maybe it was overcharged,  Maybe it shed a jacket from the previous round, or otherwise built up a layer that started constricting the barrel.  Maybe the previous round was a squib.  It would be good if the OP showed what the fired casings looked like, particular the heads.  It would be good if he picked up and inspected all of them, to see if maybe there's one of two of the latest ones, that started doing this.  The brass is butter-soft, so if there's an overpressure, it's going to flow easier than other brands will.  What we can be sure of though is:
-The cheap-crap plastic receivers had nothing to do with this.
-That's not an OOB.
-There was a major over-pressure that exceeded the rating of the brass.
-It wasn't a .300 BO related Kaboom (first non-.300 BO related one in the last 4 Kabooms I've read up on!)

Here's what I'd like to see from OP.
-Inspect all the remaining ammo for any sign of copper discoloration on the necks and around the primers (sign of powder decomposition).
-Pull one round apart, and inspect the powder for noxious odor (very strong and stinging to the nose - think nitric acid fumes), clumpyness, wetness, stickyness, or other indicators of decomposition.  Also, post a photo of the powder.
-Take a micrometer to about 20 or so remaining rounds bullets, and see if there's much variation in bullet diameter.
-Inspect all the fired brass, and in particular the heads, for sign of pressure building up, split necks, bent rims, extrusion into the ejector space, headswipes, or other unusual sign.
-Push a cotton patch down the barrel and inspect carefully the patch as well as what it pushes out, for any sign of any metal shavings or other metal debris (there should be none in the barrel)
-Run fingers down the barrel and carefully feel for any swells
-A Rockwell hardness comparison test of this brass vs other brass would be nice, but that's probably asking a bit much!  That said, take a fired casing, and crush the head in a vice; and repeat that test with US fired brass, and report if there's any obvious difference in force it took.
-Report back on the previous shot.  Was report, recoil, and cycling normal, and was impact in target observed - and normal?

Carbon 15's are well-known to be time bombs. Eventually something in the cheap plastic receivers gives way. You're lucky your son isn't blind or missing fingers.

Buy a decent rifle. Daniel Defense, BCM, LaRue, FN- all these are lifetime guns that have been proven reliable and durable many times over.