Well, that sucked.

[darkfader]

So brand new M4 build went kaboom after about 4 mags. I didn’t beat on the thing at all. Ran a mag and let it cool down. Yes each mag was a single FRT burst but the rifle took breaks between mags, and ran perfectly until this happened.

During the fourth mag there was a double feed which was cleared but a live round stayed in the chamber. I just dropped the bolt on that live round and sent it. Bad move. Carnage is as follows.

The case is stuck in the chamber pretty good. Any tips on getting that out? If I can save the barrel that would be good. I guess I notify the ATF that this receiver is destroyed and remove it from the NFA?

I’ve got other shit to do today but if you guys can off any advice, I’d appreciate it. I’ll check back in later for sure. Spent a long time and some decent money on this build so this is disappointing to say the least. It looks like BCG, and upper and lower are definitely trash, but most everything else looks ok to include the DTT FRT. I’d like to get the case out of this barrel.

I can hear a piece of metal inside the suppressor as well and there was definitely a strike on the end cap. I’ll contact OCL about taking a look at it I guess.

 

[Bluedog82]

What ammo were you using?

 

[Redlion]

Wow. Looks like you got the stuck casing out.

 

[matt33]

I don't see anything worth saving there. Personally, I would trash it and move on.

 

[darkfader]

What ammo were you using?

Winchester M193 55 gr

Wow. Looks like you got the stuck casing out.

No, just the head of the case came out. The body of the case is still in the chamber

 

[diggler1833]

Well that definitely sucks.

On the bright side, you still have your eyesight and fingers to be able to post about it.

Other than probably some furniture and supporting pieces, I'd probably start over from the ground up.

 

[whatsupdoc]

Scrap the barrel also, what possible reason would you have to take a chance with a barrel that may now
have a flaw and destroys another rifle.

 

[joe777]

A double feed with two live rounds? Need more info on what actually happened there.

It blew up and you also got a baffle strike? Maybe a barrel obstruction?

 

[sloporsche]

Winchester M193 55 gr

No, just the head of the case came out. The body of the case is still in the chamber

Decades ago i learned a backyard trick for pulling broken cases on 7.62x39 where a 3/8's tap is just slid into the case and cocked slightly with a finger while push a cleaning rod into the barrel and tapping it out ,it has never failed to grip and the rod pushes it out . 556 might require a 5/16 tap or similar .

 

[Im2bent]

You can try jamming a large brass cleaning brush into the case and see if it will pull out.

 

[carbonbased]

Was the suppressor loose?

Just confirming-you dropped the bolt, pressed the trigger, and then ?

 

[Im2bent]

A double feed with two live rounds? Need more info on what actually happened there.

It blew up and you also got a baffle strike? Maybe a barrel obstruction?

Where are you seeing a baffle strike?

 

[carbonbased]

Where are you seeing a baffle strike?

I can hear a piece of metal inside the suppressor as well and there was definitely a strike on the end cap.

OP mentions it.

 

[loveha]

A dual edge easy out. Not the kind that you screw in, but ones that have 4 long hard edges. But just about anything that will bite and twist the brass while you pull should work.

If it was me, I would not bother saving the barrel. Wasn't anything like a cut rifled custom barrel I am assuming.

 

[Hecouldgoalltheway]

Take a can of canned air, turn it upside down and get that brass ice cold. It will slide right out.

 

[91Eunozs]

I’d suspect barrel obstruction too… squib round prior to the fte malfunction maybe?

Would also explain the fte/double feed.

Edit: and just to confirm, there’s no way a 300BLK round got mixed in, right? That looks a lot like guns I’ve seen where a 300BLK round was jammed into a 5.56 chamber when they grabbed the wrong magazine.

There’s a reason I use completely different mags for different calibers on my ARs; have several uppers chambered in different calibers, and need to put as many safety mechanisms as possible in place, especially if we’re doing a range session with multiple calibers

Normally make it a point to only take one caliber out at a time, even for the other people I’m shooting with, but we sometimes have different uppers to sight in after a re-barrel, or a new optic, etc. For my group we use:

.223/5.56 gets Magpul and GI mags

300BLK is only loaded into Lancer mags that are also clearly marked as 300BLK…can feel the difference at night too when out shooting pigs on NVGs/thermal

450BM and 6.8 SPC both have mags unique to their round, I’m pretty much the only person in my group that ever shoots these calibers though, so not as big of a concern as 5.56 vs. 300BLK.

 

[91Eunozs]

Also, unless you SBR’d the receiver, why would you need to remove it from the NFA?

 

[MO Fugga]

I’d suspect barrel obstruction too… squib round prior to the fte malfunction maybe?

Would also explain the fte/double feed.

Edit: and just to confirm, there’s no way a 300BLK round got mixed in, right? That looks a lot like guns I’ve seen where a 300BLK round was jammed into a 5.56 chamber when they grabbed the wrong magazine.

There’s a reason I use completely different mags for different calibers on my ARs; have several uppers chambered in different calibers, and need to put in as many safety mechanisms as possible:

.223/5.56 gets Magpul and GI mags
300BLK is only loaded into Lancer mags that are also clearly marked as 300BLK…can feel the difference at night too when out shooting pigs on NVGs/thermal
450BM and 6.8 SPC both have mags unique to their round.

Same. Lancer for 300, pmag for 556, GI for 458 socom.

 

[Markbsae]

Edit: and just to confirm, there’s no way a 300BLK round got mixed in, right?

I bought a box of LAX 5.56x45 reloads and found 9 rounds of 220 grain .300 blackout. It's definitely possible

 

[Mean_Man]

So brand new M4 build went kaboom after about 4 mags. I didn’t beat on the thing at all. Ran a mag and let it cool down. Yes each mag was a single FRT burst but the rifle took breaks between mags, and ran perfectly until this happened.

During the fourth mag there was a double feed which was cleared but a live round stayed in the chamber. I just dropped the bolt on that live round and sent it. Bad move. Carnage is as follows.

The case is stuck in the chamber pretty good. Any tips on getting that out? If I can save the barrel that would be good. I guess I notify the ATF that this receiver is destroyed and remove it from the NFA?

I’ve got other shit to do today but if you guys can off any advice, I’d appreciate it. I’ll check back in later for sure. Spent a long time and some decent money on this build so this is disappointing to say the least. It looks like BCG, and upper and lower are definitely trash, but most everything else looks ok to include the DTT FRT. I’d like to get the case out of this barrel.

I can hear a piece of metal inside the suppressor as well and there was definitely a strike on the end cap. I’ll contact OCL about taking a look at it I guess.

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Who made that bolt and carrier?

Also while I can't tell for sure from these pictures but the lower might could be saved if you know a good TIG welder. I am one, but I doubt you live local to me. Is it ballooned out or just cracked in the magwell?

 

[darkfader]

Thanks for the replies gents. Let’s see if I can address everything in one go.

Definitely not a custom barrel so I will err on the side of caution and it’s getting scrapped along with the upper and lower and bcg. Not sure why my cheap ass was worried about saving the barrel.

There was no obstruction because I used a cleaning rod to attempt to remove the case and the head of the case came right off with very little resistance and the rod slid right through. The rest of the case is in the chamber still.

The actual event went as follows, my stepson was firing in FRT mode, when it stopped and he looked at me and said “I have a jam”. I took the rifle, looked in the ejection port and saw bcg held rearward by a live round trying to feed into another live round in the chamber. I dropped the mag, locked the bcg back, allowed the double fed round to drop out of the mag well, sent bcg forward onto chambered live round, squeezed the trigger and kaboom.

The lower is an NFA registered SBR. I assume I should notify the ATF to remove the rifle from the registry and destroy this thing beyond repair. After thinking about it a little more clearly, I certainly don’t want to attempt to repair any of this thing. I’ll just save the basic parts that weren’t affected like buffertube and stock and trigger pack.

 

[91Eunozs]

Still think it could have been a squib load on the round prior… the over pressure could have sent both bullets out the barrel.

Or possibly a very overcharged case… or even more likely, the bolt wasn’t all the way into battery when it fired. Starting to think there was a partial case stuck in there already, and that didn’t allow the next round to seat in the chamber properly.

Edit: and looking at that case head, that’s a huge impact crater from the ejector. Clearly a NATO head stamp, so assume the ammo was 5.56. was the barrel chambered in 5.56 or was it a .223 chamber? Maybe 223 Wylde?

Any extraction issues prior to this? FTEs, or cases with the heads ripped off?

Maybe?

And bummer about the SBR tax stamp…yeah, that sucks. My last couple of Form one SBRs came back pretty quick though, so silver lining I guess. :-/

 

[carbonbased]

Thanks for the replies gents. Let’s see if I can address everything in one go.

Definitely not a custom barrel so I will err on the side of caution and it’s getting scrapped along with the upper and lower and bcg. Not sure why my cheap ass was worried about saving the barrel.

There was no obstruction because I used a cleaning rod to attempt to remove the case and the head of the case came right off with very little resistance and the rod slid right through. The rest of the case is in the chamber still.

The actual event went as follows, my stepson was firing in FRT mode, when it stopped and he looked at me and said “I have a jam”. I took the rifle, looked in the ejection port and saw bcg held rearward by a live round trying to feed into another live round in the chamber. I dropped the mag, locked the bcg back, allowed the double fed round to drop out of the mag well, sent bcg forward onto chambered live round, squeezed the trigger and kaboom.

The lower is an NFA registered SBR. I assume I should notify the ATF to remove the rifle from the registry and destroy this thing beyond repair. After thinking about it a little more clearly, I certainly don’t want to attempt to repair any of this thing. I’ll just save the basic parts that weren’t affected like buffertube and stock and trigger pack.

There’s something funny, still, about that baffle strike.

 

[brazz04]

I bought a box of LAX 5.56x45 reloads and found 9 rounds of 220 grain .300 blackout. It's definitely possible

I have bought a lot of their ammo, that's definitely alarming and something I'll certainly look out for.

 

[tylerradke]

My guess is out of battery slightly due to the case head being deformed by the second round. I don't think the bolt would have locked with the case head being dinged that bad. Not sure on the end cap strike though. That's a tough one. Maybe can walked loose during the mag dumps and was struck before the failure.

 

[darkfader]

Still think it could have been a squib load on the round prior… the over pressure could have sent both bullets out the barrel.

Or possibly a very overcharged case… or even more likely, the bolt wasn’t all the way into battery when it fired. Starting to think there was a partial case stuck in there already, and that didn’t allow the next round to seat in the chamber properly.

Edit: and looking at that case head, that’s a huge impact crater from the ejector. Clearly a NATO head stamp, so assume the ammo was 5.56. was the barrel chambered in 5.56 or was it a .223 chamber? Maybe 223 Wylde?

Any extraction issues prior to this? FTEs, or cases with the heads ripped off?

Maybe?

And bummer about the SBR tax stamp…yeah, that sucks. My last couple of Form one SBRs came back pretty quick though, so silver lining I guess. :-/

Barrel was a 14.5” SOCOM profile barrel chambered in 5.56. I believe the bcg was fully in battery because I had to beat on the ears of the charging handle with a hammer to get the thing out of the lugs. It was clearly locked up in the lugs when I first separated the upper from the lower.

 

[kli3309]

...The lower is an NFA registered SBR. I assume I should notify the ATF to remove the rifle from the registry and destroy this thing beyond repair...

Torch cut (or crush or shred) receiver per ATF guidelines then notify them and request removal from the registry.

How to Properly Destroy Firearms | Bureau of Alcohol, Tobacco, Firearms and Explosives

How to Properly Destroy Firearms What are ATF’s Acceptable Destruction Procedures? Use an oxy/acetylene torch (not band sawed) Must remove at least ¼ inch of metal per cut Must be made at angles and completely sever the receiver in at least 3 critical locations (specified by model) Acceptable...

www.atf.gov