Quoted: Tag for updates...

I'm glad to hear you weren't hurt. Thank you for posting this.

I came here via a link from ARFCOM's G.D. forum.

I think the lesson here would be to inspect all of your ammo, and if there is any anomolies, ditch it.  It is better to be safe than sorry.

I won't shoot Black Hill remanufactured ammo.
The last big batch I bought in 1999 had cracked case mouths, weak loads and a couple had primers not seated or else pushed in too far.

The same reason why I won't shoot Miwall reloads either.
I had one round squib in a 16 inch Clot HBAR, the next round blew it out of the barrel.
I was covered in bullet schrapnel and so was the guy next to me.
The gun didn't kaboom thought, best I can figure that the squib round made it to almost the end of the barrel and the following round blew it up and out.

I am glad to hear that you are ok.

Classic case failure.  Since this was (pseudo)M855, it is possible both the outcome (case failure) and the observed symptoms (bullets backing out) have a common nexus in an overcharge.  But I suspect bad brass over all.

The M855 projectiles (AKA SS109 bullets) are very long and as such, deep seated to the point of intruding on case volume.  If MCC used a slower propellent, it is possible they are running compressed loads.  First question:  Can you hear propellent when a cartridge is shaken?

This leads to the next possibilty.  If the charge is compressed, it is entirely possible for an over maximum charge.  This cannot be proven as the immediate evidence is gone, that being the propellent that caused this energy release.  But the remaining ammunition could be broken down with each charge carefully weighed, making a statistical probability based on the samples.  I also doubt this based on the fact you have a bullet stuck in the bore.  This means there was sufficient propellent to ignite and develop at least 20,000 PSI, probably closer to 55,000 PSI yet the pressure was lost rapidly enough to retain the bullet in the bore.  Case failure happened before peak pressure had developed, otherwise the bullet would have left the bore.

Most likely is the situation of a weak case.  Second question:  What is the headstamp of the case head in question?  There have been examples of LC brass being bad but this is unlikely source since they are all Federal XM line.  If MCC is using LC brass, it probably comes from DRMO auction sources and is from US Military training.

If it is a S&B case head, that is the problem.  These are very weak cases.  Also applies if its an FC as their American Eagle from 6-8 years ago had this problem.  The weak case from FC is due to excessivly thin webs with thick walls.  The AR and similar rifles have an unsupported chamber condition with these cases.

Excessive pressure is probably not an issue unless the primer shows evidence of this.  If the primer is intact without preforation at the firing pin impression, pressure was not a factor.  Now the primer will most probably be loose in the pocket due to the deformation of the rupture.  Be careful when removing  the brass from the bolt.  The loss of the extractor would definitley cause at least part of the primer sides to be lost but you could have the central part remaining.  

Glad you are ok. Sorry about your rifle.

I had a similiar, but not nearly as bad, kB a couple years ago.....disassembled the mag and blew it and the remaining ammo all over my driveway.  It was old surplus ammo, and after inspected the remaining rounds, I found about 1 in 20 with the bullet loose.

A 68 grain bullet doesn't take up nearly as much case volume as a 75 or 77.  I'll go out on a limb and say that what happened was the bullet was shoved back in the case on chambering.  Upon firing, the set back bullet results in severe overpressure, with subsequent case failure.  

If you knew the bullets were loose in the cases, you are at fault since YOU chose to fire it anyway.  Not trying to be a dick, but that's the way I see it.    

Quoted: I had a similiar, but not nearly as bad, kB a couple years ago.....disassembled the mag and blew it and the remaining ammo all over my driveway.  It was old surplus ammo, and after inspected the remaining rounds, I found about 1 in 20 with the bullet loose. A 68 grain bullet doesn't take up nearly as much case volume as a 75 or 77.  I'll go out on a limb and say that what happened was the bullet was shoved back in the case on chambering.  Upon firing, the set back bullet results in severe overpressure, with subsequent case failure.   If you knew the bullets were loose in the cases, you are at fault since YOU chose to fire it anyway.  Not trying to be a dick, but that's the way I see it.

But a 62 grain, steel penetrator M855 bullet does.

Quoted: WOW!!!  I didn't know that something like this could happen to this extreme.  I just bought 1k rounds of Maine C.C. too I used to place my hand under 20rnd mags at times when shooting...not anymore.

Please read the tacked thread in the ammo forum for review and reference,  before a purchase.  MCC is one of the worst rated ammunition suppliers that has been reviewed.

J_Smith - please post your results in the MCC review thrad - that thread wont get archived and can serve as a warning to others.  Maybe MCC has addressed their QC/QA in the last 6-8 years, then again, maybe not.  There have been lots of bad MCC threads over time, but they all get archived eventually.  It would be good to have this experience in the review thread.

www.ar15.com/forums/topic.html?b=3&f=16&t=245703

Holy crap.......Glad to see you made it out alright. Its good to have you digits and its also good to have your "boys" too, you were sitting you know......


If the company doesnt settle with you, let the word out I know I wont be buyin off of them.

Carter

tag for outcome

Quoted: Black Hills seems to be outstanding?

Black Hills spends more money inspecting the components, the process, and the finished ammo than they do actually assembling the ammo.    They inspect EVERY SINGLE primer.   If you have any questions about their quality call them.

Quoted: I won't shoot Black Hill remanufactured ammo. The last big batch I bought in 1999 had cracked case mouths, weak loads and a couple had primers not seated or else pushed in too far.

that is interesting to hear.   Did you ever contact them for a settlement?

I know they don't get the various mil/ leo contracts they do for producing poor ammo.

Quoted:  I'm debating what is the best course of action - contact the company first or contact a lawyer - or if I even have a solid legal case. I bought this ammunition 6-8 years ago and no longer have the original receipt or packaging.

I'll bet a lawyer can get something from you CC company showing you purchased the ammo and something from the shipper saying who sent it and that it was delivered.

Any way to get some not so shitty pictures?

Quoted: Could it been a SQUIB?

You hit the nail on the head, IMHO.

J_Smith - Did the cartridge fired immediately prior to the kaboom seem like it was underpowered? I ask because this seems like that cartridge's bullet might have become lodged in the barrel, creating an obstruction. When the fatal cartridge was fired, the bullet would have gone into the barrel and also become lodged, thereby eliminating anywhere for the expanding gas to go. Chamber pressure is something like 55,000 PSI and the only way for it to be released would be for the bolt & carrier to move backward. Since it appears the bolt carrier was in the rearward position, I'm assuming that allowed the expanding gas pressure to blow out the sides of the upper receiver. The ejection port probably saved the day once the bolt carrier passed it, because it would have been the first available (safe) escape route for the gas.

Perhaps you might send the rifle to be examined/x-rayed to see if there's more than one bullet lodged in the barrel. I am familiar with a very good engineering firm in my town that could do such work, but I have no idea what the cost would be. I'm sure any decent firm could do it - you might find one local to you.

An alternative would be, if you can, to insert a cleaning rod into either end of the barrel and measure how far it goes in until obstructed. Mark a line on the rod at the stop point, then remove the rod, align the mark at the end of the barrel (outside the barrel) and mark the side of the barrel at the end of the cleaning rod. That'll show you where the bullet's lodged. Then do it for the opposite end of the barrel and compare where the two marks end up. If they're more than the length of one bullet, it's likely there's two there.

Quoted: Classic case failure.

How are you ruling out an OOB situation?   The way the corners of the bolt lugs are chipped off, it looks like it may have fired with the bolt just starting to lock.   In that situation, case failure is caused by the kaboom, not the other way around....

tagged for outcome, glad you were not hurt.

Quoted: Quoted: Could it been a SQUIB? You hit the nail on the head, IMHO. J_Smith - Did the cartridge fired immediately prior to the kaboom seem like it was underpowered? I ask because this seems like that cartridge's bullet might have become lodged in the barrel, creating an obstruction. When the fatal cartridge was fired, the bullet would have gone into the barrel and also become lodged, thereby eliminating anywhere for the expanding gas to go. Chamber pressure is something like 55,000 PSI and the only way for it to be released would be for the bolt & carrier to move backward. Since it appears the bolt carrier was in the rearward position, I'm assuming that allowed the expanding gas pressure to blow out the sides of the upper receiver. The ejection port probably saved the day once the bolt carrier passed it, because it would have been the first available (safe) escape route for the gas. Perhaps you might send the rifle to be examined/x-rayed to see if there's more than one bullet lodged in the barrel. I am familiar with a very good engineering firm in my town that could do such work, but I have no idea what the cost would be. I'm sure any decent firm could do it - you might find one local to you. An alternative would be, if you can, to insert a cleaning rod into either end of the barrel and measure how far it goes in until obstructed. Mark a line on the rod at the stop point, then remove the rod, align the mark at the end of the barrel (outside the barrel) and mark the side of the barrel at the end of the cleaning rod. That'll show you where the bullet's lodged. Then do it for the opposite end of the barrel and compare where the two marks end up. If they're more than the length of one bullet, it's likely there's two there.

I checked the bore using a cleaning rod cable. Where the blockage is at - doing measurements - there is only room for one projectile - so the round is from the fired casing - no additional Squib round. Thanks for the extra input though - its good that I checked on it.

That's one for posterity. Any way to get some better photos when you get a chance? Photos of that damage speak volumes to anyone thinking of using inferior ammo just to save a few pennies.

BTW nice scope. I just got one

Finding the bullet lodged in barrel just beyond chamber is consistent with a primary brass failure at acceptable pressure, as noted.  It is also consistent with secondary brass failure due to excessive/unacceptable pressures.  This latter can occur in the event of pistol powder substitution.  In such a case the bullet cannot advance quickly enough ahead of the sudden excessive pressure spike.  

In either case the action will not have opened normally by way of gas impingement via carrier key b/c port pressure never rose above zero.

Sam

Quoted: Quoted:  I'm debating what is the best course of action - contact the company first or contact a lawyer - or if I even have a solid legal case. I bought this ammunition 6-8 years ago and no longer have the original receipt or packaging. I'll bet a lawyer can get something from you CC company showing you purchased the ammo and something from the shipper saying who sent it and that it was delivered.

Good idea but I purchased this 6-8 yrs ago so I'm SOL in that department. I think I bought the case of ammunition at a Machine Gun shoot if I remember correctly. So possibly before I joined the Army...and I'm Coast Guard now. There may be some Statue of Limitations or something - I dont know. In any case - no receipts or other paperwork here. Yuck.

Was the bolt still locked and you had to manually turn the bolt and pull it out of the barrel extension, or was it already unlocked when you started to inspect the damage?

Quoted: Quoted: Classic case failure. How are you ruling out an OOB situation?   The way the corners of the bolt lugs are chipped off, it looks like it may have fired with the bolt just starting to lock.   In that situation, case failure is caused by the kaboom, not the other way around....

OOB firing will drive the bolt and carrier completly back.  The original poster had to hammer the bolt and carrier out of the upper.  The bolt and carrier never left battery.

When the case head ruptures, sending the extractor out of its position, the bolt usually cracks and expands into the barrel extension locking lugs, preventing all movement.

Because of this lock up and the loss of the bottom of the carrier, where the bolt rides, the bolt is now out of alignment.  When the original poster used a hammer and drift to pull the carrier and bolt, the onle lug was out of alignment, causing part of the damage.

That there is still part of the case head in the bolt is proof enough this is not an OOB.

Quoted: Quoted: Quoted: Classic case failure. How are you ruling out an OOB situation?   The way the corners of the bolt lugs are chipped off, it looks like it may have fired with the bolt just starting to lock.   In that situation, case failure is caused by the kaboom, not the other way around.... OOB firing will drive the bolt and carrier completly back.  The original poster had to hammer the bolt and carrier out of the upper.  The bolt and carrier never left battery. When the case head ruptures, sending the extractor out of its position, the bolt usually cracks and expands into the barrel extension locking lugs, preventing all movement. Because of this lock up and the loss of the bottom of the carrier, where the bolt rides, the bolt is now out of alignment.  When the original poster used a hammer and drift to pull the carrier and bolt, the onle lug was out of alignment, causing part of the damage. That there is still part of the case head in the bolt is proof enough this is not an OOB.

Exactly as you describe. You articulate the situation better then I can. I'll try to get better pictures up within the next day if I can - I may need a different camera - my digital one is sucking.

Wow.  How is it possible that a company like this is still in business?  I'm afraid to order form HSM.  One of my Hornady 75 Grain 5.56 TAP rounds once had something similar but not as bad.  I just heard a poof and my gun smocked.  After inspecting what happened, it looked like it was a cook-off.  I believe that is what it is called.  No damage to anything on my rifle though.  I took the bullet out with some help from some guys at the range and continued shooting.  Some of the guys at the range were amazed that it happened though.  Just goe to show that failures can happen with any ammo.  Glad you're ok though.

Quoted: Wow.  How is it possible that a company like this is still in business?  I'm afraid to order form HSM.  One of my Hornady 75 Grain 5.56 TAP rounds once had something similar but not as bad.  I just heard a poof and my gun smocked.  After inspecting what happened, it looked like it was a cook-off.  I believe that is what it is called.  No damage to anything on my rifle though.  I took the bullet out with some help from some guys at the range and continued shooting.  Some of the guys at the range were amazed that it happened though.  Just goe to show that failures can happen with any ammo.  Glad you're ok though.

Cook-offs are when the chamber temperature is so high, that the powder charge is ignited.  It is extremely rare - because it is damned near impossible to get the chamber temps high enough in an AR15.  In the M16, with extremely fast mag changes, it is possible.  Unless you had just fired two beta mags, back to back, bumpfiring, it is unlikely you experienced a cookoff.  

In addition - a typical cookoff fires the round normally.  You wouldnt notice any different sound or smoke.  (other than the smoke pouring off your handguards.... if the chamber was really that hot!)

Sounds like you had a case head failure, or a defective round.

Cook-offs are when the chamber temperature is so high, that the powder charge is ignited.  It is extremely rare - because it is damned near impossible to get the chamber temps high enough in an AR15.  In the M16, with extremely fast mag changes, it is possible.  Unless you had just fired two beta mags, back to back, bumpfiring, it is unlikely you experienced a cookoff.  

In addition - a typical cookoff fires the round normally.  You wouldnt notice any different sound or smoke.  (other than the smoke pouring off your handguards.... if the chamber was really that hot!)

Sounds like you had a case head failure, or a defective round.

Thanks, i didn't know exactly what it was called.

I have read some replies stating something to the effect of " I am only going to use newly manufactured, commercial stuff from now on."

I also realize that some surplus ammo (.308 mentioned specifically) has been bad.

To each his own, of course, but this really has no bearing on some of the better known surplus 5.56, right?  Like the SA stuff that was so popular, and the currently available surplus from Guatemala ?

NEVER shoot subpar ammo, it's an expensive lesson but I'm sure a lot of people wouldn't believe it without seeing pictures. Thanks for a good post & I hope they pay for the damage.

QUOTE....."" My biggest problem with Maine Cartridge Company ammo is that many bullets didnt seem to be seated properly. On several occasions I had fired my midlength AR's with the ammo and the projectile got pushed back into the casing. It annoyed me and I attributed it to poor quality control. That aside, I took the "It will never happen to me" approach and intended to burn up the rest of the ammo because I couldnt possible see the shit exploding and ripping a case apart. Well - we see what happens when you don't pay attention to warning signs. ""
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Word of caution after the fact!   If the ammo is causing bullet setback on numerous occasions,  this is the time to stop firing. This  KB probably was caused by a bullet setback that was chambered and fired.

tag for outcome
Glad you are all right

Damn!  That's quite a lesson.  

That's 1 reason I don't shoot reloads unless they are my own, regardless of the companies reputation on reloaded ammo.  Seems like the brass was weak and might have been reloaded a few times too many.  

Quoted: That's 1 reason I don't shoot reloads unless they are my own, regardless of the companies reputation on reloaded ammo.  Seems like the brass was weak and might have been reloaded a few times too many.

From what I have been told, the suspect ammo was of highly varied headstamps and it was of 1999-2001 vintage.  It probably had one American Eagle brass (headstamped "FC") mixed in.  This exact same brass KBed my AR in 1999, only it was one of my own reloads.

Reloading brass too many times will not result in such a failure, the case fails further up and very little gas leaks.  But the most common problem with oft used brass is loose primer pockets, a functional issue and eventually erodes the bolt from gas leakage but nothing catastrophic.


It is best to forgo using ANY reloads of brass with an FC or S&B headstamp.  TZZ/IMI and LC are all GTG.

Quoted: Quoted: That's 1 reason I don't shoot reloads unless they are my own, regardless of the companies reputation on reloaded ammo.  Seems like the brass was weak and might have been reloaded a few times too many.   From what I have been told, the suspect ammo was of highly varied headstamps and it was of 1999-2001 vintage.  It probably had one American Eagle brass (headstamped "FC") mixed in.  This exact same brass KBed my AR in 1999, only it was one of my own reloads. Reloading brass too many times will not result in such a failure, the case fails further up and very little gas leaks.  But the most common problem with oft used brass is loose primer pockets, a functional issue and eventually erodes the bolt from gas leakage but nothing catastrophic. It is best to forgo using ANY reloads of brass with an FC or S&B headstamp.  TZZ/IMI and LC are all GTG.

Hmm my latest batch of Georgia Arms Canned Heat has a lot of FC and S&B headstamps.

Quoted: Quoted: Quoted: That's 1 reason I don't shoot reloads unless they are my own, regardless of the companies reputation on reloaded ammo.  Seems like the brass was weak and might have been reloaded a few times too many.   From what I have been told, the suspect ammo was of highly varied headstamps and it was of 1999-2001 vintage.  It probably had one American Eagle brass (headstamped "FC") mixed in.  This exact same brass KBed my AR in 1999, only it was one of my own reloads. Reloading brass too many times will not result in such a failure, the case fails further up and very little gas leaks.  But the most common problem with oft used brass is loose primer pockets, a functional issue and eventually erodes the bolt from gas leakage but nothing catastrophic. It is best to forgo using ANY reloads of brass with an FC or S&B headstamp.  TZZ/IMI and LC are all GTG. Hmm my latest batch of Georgia Arms Canned Heat has a lot of FC and S&B headstamps.

Cull them and use them in your bolt action rifle.  After my KB in 1999 and ultimate discovery of the root cause, I started sectioning brass I found on the range, just to see what was safe and what wasn't.  Only S&B and FC had thin webs.  Not every case was weak but only these two brands had weak cases.

The FC I got from Federal Premium was NOT weak but it had the exact smae headstamp as the American Eagle.  You could have brass from FC premium but the only way to know is to pull every one.

On the S&B, I would not put any of that brand in my rifles.  

WOW

Glad you are OK.

Quoted: Quoted: Quoted: Quoted: That's 1 reason I don't shoot reloads unless they are my own, regardless of the companies reputation on reloaded ammo.  Seems like the brass was weak and might have been reloaded a few times too many.   From what I have been told, the suspect ammo was of highly varied headstamps and it was of 1999-2001 vintage.  It probably had one American Eagle brass (headstamped "FC") mixed in.  This exact same brass KBed my AR in 1999, only it was one of my own reloads. Reloading brass too many times will not result in such a failure, the case fails further up and very little gas leaks.  But the most common problem with oft used brass is loose primer pockets, a functional issue and eventually erodes the bolt from gas leakage but nothing catastrophic. It is best to forgo using ANY reloads of brass with an FC or S&B headstamp.  TZZ/IMI and LC are all GTG. Hmm my latest batch of Georgia Arms Canned Heat has a lot of FC and S&B headstamps. Cull them and use them in your bolt action rifle.  After my KB in 1999 and ultimate discovery of the root cause, I started sectioning brass I found on the range, just to see what was safe and what wasn't.  Only S&B and FC had thin webs.  Not every case was weak but only these two brands had weak cases. The FC I got from Federal Premium was NOT weak but it had the exact smae headstamp as the American Eagle.  You could have brass from FC premium but the only way to know is to pull every one. On the S&B, I would not put any of that brand in my rifles.

Great.......I can't find any of the S&B in the can, I have a lot of FC.  I also have some marked: Malay 556 82

Malay 556 is fine for all the years I found, including 82.  IIRC, they were sold the old TW AAP equipment after it was upgraded to SCAMP.  These SCAMP machines were then transfered to LC in the middle 1970's.

Tagging this to see how it turns out.  


Glad to hear  you are ok Jon!

Update - I called the company and the owner said to ship him the rifle along with the ammunition and he would inspect it to determine the cause. (To me its pretty obvious what happened). Any thoughts on this? Should I ship the rifle registered US mail or another method?? And can ammunition only be shipped via UPS?? Thanks.

Quoted: Update - I called the company and the owner said to ship him the rifle along with the ammunition and he would inspect it to determine the cause. (To me its pretty obvious what happened). Any thoughts on this? Should I ship the rifle registered US mail or another method?? And can ammunition only be shipped via UPS?? Thanks.

UPS for both.  The rifle is non-operative.  Remove the scope and send it insured for replacement value of the rifle before it KBed.

Commercial reloaders must carry insurance for this exact purpose.  It would be cool if you could see what the headstamp on the brass is.

Don't send them together though.

Mailed insured today. I spoke to the manufacturer and he seems to have a preconceived belief that the bolt didnt close all the way Nothing that I or others have seen on the rifle would indicate that it was "out of battery". And thus the finger pointing contest beings. Personally, I don't buy it from evidence set forth - but he said he would look at it. I will hopefully have some update next week.

Damn Smitty, glad to see you are ok...

Sorry about the rifle...