M-4 failure

Discussion in 'AR-15 Discussion' started by Dzscubie, Jun 8, 2011.

  1. Dzscubie

    Dzscubie New Member

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    We had an incident a last week with one of our officers and his personal M-4. It is believed that a round “telescoped” into the casing and caused such an increase in preassure that it resulted in the following catastrophic failure. Officer was not hurt but weapon is a total loss.

    Scubie
     

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  2. Dzscubie

    Dzscubie New Member

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    Next set of photos....
     

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  3. Dzscubie

    Dzscubie New Member

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    last set.........
     

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  4. VitSports6

    VitSports6 New Member

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    I'm trying to wrap my head around how this happened, But I don't understand the term "telescoping"
    CRAZY none the less :eek:
     
  5. diggsbakes

    diggsbakes New Member

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    Wow, that's amazing! Glad he wasn't hurt, but I don't get "telescoping" either. Enlighten us.
     
  6. Dzscubie

    Dzscubie New Member

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    Sorry guys sometimes I think everyone knows what I’m thinking when I’m thinking it.

    Telescoping is when the round (bullet) is forced down into the neck of the cartridge (brass case) kind of like a old time telescope or a collapsible baton. This causes an increase in pressure when fired. If the bullet is not aligned with the neck opening or completely out of the neck and in the casing then you have a catastrophic failure as the round has no where to go.

    I’ve heard of these but never witnessed one myself.


    Scubie
     
  7. hydrashok

    hydrashok New Member

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    Great post, scubie!!!

    After looking at the pictures, I was wondering if the lower was also damaged?
     
    Last edited: Jul 7, 2011
  8. CA357

    CA357 New Member Supporter

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    Wow, that's nasty. I'm glad the officer is alright.
     
  9. Gatekeeper

    Gatekeeper New Member

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    Saw a kaboom on another forum recently that caused similar damage.
    It was caused by an apparent squib round lodging in the barrel just in front of the chamber. Shooter didn't hear the squib and treated the stoppage like a fail to fire.
    Tap-Rack-BOOM. Actually blew the flat top rail and optic off the rifle.:eek:
    Shooter was also unhurt
     
  10. Fisherking

    Fisherking New Member

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    Just a cupla questions what amo was he using or was he rolling his own?
    Thanks F.K.
     
  11. Car54

    Car54 New Member

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    So the round that was being used was factory Remington HP's? I remember not to long ago some Ranger ammo was loaded wrong and was causing some AR's to blow up.

    Glad that everyone is okay.
     
  12. Dillinger

    Dillinger New Member

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    I've heard of this happening, but never have seen any evidence of it actually happening from such a reliable source.

    Thanks for posting Scubie, I know you have had a ton of folks looking at it. Is there a consensus that this was truly a one of a time issue, or perhaps a final stressor after thousands of rounds of field use? Any stress cracks that obviously expanded with the initial increase in pressure? Or just gone from flat factory to complete disaster?

    Many thanks for this hands on intel. Any after action or armory inspection results would be greatly appreciated.

    JD
     
  13. texaswoodworker

    texaswoodworker New Member

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    Wow, That is a whole lot of damage. Glad the officer was not hurt.
     
  14. synical

    synical New Member

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    Is that due to not using the forward assist to make sure the round was chambered correctly?
     
  15. JonM

    JonM Moderator

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    No an ar15 cant fire out of battery.

    Looks like the bore coulda been blocked. By either a squib or oil or even piece of a patch. Ive seen that on issue m16 where the soldier left part of the patch in the barrel.
     
  16. Quentin

    Quentin New Member

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    Scubie said in the OP that it is believed the bullet somehow collapsed back into the casing. No way to be 100% sure, the evidence kaboomed.

    The round could have hit the feedramp hard then chambered with a squashed bullet or maybe physical damage to the cartridge before loaded in the mag. Could have even been manufactured wrong. Probably a one time thing to that batch of ammo. Goes to show you need to glance at your ammo as you load magazines and pay attention to the bore and the report of each shot. And if you reload, zero mistakes!
     
  17. dnthmn2004

    dnthmn2004 New Member

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    I guess that is a total loss. WOW!

    Nice to hear the officer is alright after that explosion.
     
  18. Sniper03

    Sniper03 Supporting Member Supporter

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    Scubie, Has he contacted Remington? I have seen three of these situations in the last several months throughout the country. And you are exactly correct in your analysis. I saw one worse than this at one of the Federal Agency facilities this year. It literally blew the upper receiver into 5 separate pieces and totally ripped the Hammer Ramp on the Carrier completely off the Bolt Carrier, banana pealed the Carrier, as well as blew the Ejector and extractor off the Bolt which it also broke at the cam pin hole. I have pictures of it also if you would like to have them e-mailed. I am not knowledgeable enough to past them on this post. It was a cleaning patch in the bore. The others were the telescoping issue. Federal had one that I know of and they immediately wrote a check and replaced the officers rifle when he called them. I think some of the problem is as you know they are running their plants 24hrs. X 7days a week at full speed. Therefore some quality issues arise as to the slight case crimp that is required on the cannular of the projectile. Yours was definitely a catastrophic even in battery.
    Thanks for the pics.

    03
     
    Last edited: Jul 7, 2011
  19. Sniper03

    Sniper03 Supporting Member Supporter

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    Moral of the story for all!

    If you ever have or see anyone with the bullet loose or pushed down into the casing even slightly!

    ******* do not shoot it! *******

    *if something ever sounds funny while you are shooting!
    Check for an unobstructed bore before you fire another round!

    Scubies thread shows exactly what can happen!

    *and you might not be as lucky as this officer!
     
  20. JonM

    JonM Moderator

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    here is my close call. just 3 months ago!!

    http://www.firearmstalk.com/forums/f20/grrr-ar-fail-41432/

    ingrained training is hard to break. but following army training of sports almost blew my AR up. if that primer was a scootch more powerful or if i didnt crimp the living sht out of my semi auto ammo the lodged round would have been further up the tube or pushed the live round deeper in the case resulting in a massive kaboom.

    nowadays i check the bore on any oddity i NEVER assume its working as intended

    when i took my texas ccw course waaaay back we had to do live fire. one guy on the line had a ruger gp100 and wasnt hitting the target. first round click second boom third boom 4 5 6 boom but 0 holes all the rounds were lodged in the bore from the first squib. one reason im leary of revolvers they will continue to fire on failure. he was just lucky that ruger built the older gp100 like a brick shthouse
     
    Last edited: Jul 7, 2011