Preliminary - Malfunction of a Flash Suppressor on a Bushmaster AR-15

Abstract:  
For no apparent reason the flash suppressor peeled back in four separate directions during the course of fire.  The officer firing the weapon and instructors close by were not injured and it did not appear
that any metal fragments separated or came loose during the incident.

Reason for Message:
This report is to alert other sites to the possibility of this malfunction. Any significant findings resulting from a manufacturer’s evaluation will be communicated.  

Event Date:.............September 29, 2004
Unit Name:..............
NSSS/A-E:..............
Turbine Manufacturer:...

Maintenance Rule Applicability:  No

Component Information (as applicable):
Manufacturer:  Bushmaster
Model Number:  AR-15
Part Number:   N/A

Description:  
While participating in an annual tactical stress fire course an officer was firing at targets with their rifle barrel positioned through a simulated defensive position.  Following the officer’s 3rd shot it was noted that the flash suppressor at the end of the barrel had uniformly peeled back in four directions.  

A cease-fire was called and the was  inspected by a qualified armorer. The officer shooting and the instructor nearby were checked for injuries with none found.  It did not appear that any metal had
separated from the suppressor when it failed.  No obstruction was believed to be in the rifle barrel and the officer clearly had the barrel through the defensive position for all three rounds fired.  A
subsequent check of all department weapons yielded no findings of any additional damaged suppressors.  The ammunition being used at the time of failure was Winchester, 45 grain, jacketed, frangible, lot# wcc04-1.

Cause(s):  Under Investigation

Corrective Action(s):
1. Flash suppressors on all other department weapons were inspected with no deficiencies identified.  

2. The incident was communicated to all personnel on the other shifts.

3. The weapon was sent to the manufacturer for further evaluation/testing.

Safety Significance:
There is potential for personnel injury to the shooter and instructor if pieces of metal flash suppressor were to become loose and airborne.

Never heard of that happening??

The officers on the site I work at don't have Bushy's, I believe.  I think they might be Colt or RRA.  I have a few friends in security and they haven't told me of any problems like that.

I wonder if one of those frangibles came apart in the bore?

Or if the end of the FS had become obstructed just before the 3rd shot?  Just a guess without knowing how the "[...]simulated defensive position" was constructed.

Quoted: Or if the end of the FS had become obstructed just before the 3rd shot?........

 +1

sounds like an obstruction to me. or an old soft vortex but it hink they widened slowly over time. not with one shot.

Were they able to verify all his shots hit the target?

My theory:  the round fragmented prematurely as it was exiting the muzzle and caused the flash suppressor to peen back.  

But I'm just this guy, y'know? ;)

Quoted: Were they able to verify all his shots hit the target? My theory:  the round fragmented prematurely as it was exiting the muzzle and caused the flash suppressor to peen back.   But I'm just this guy, y'know? ;)

Wouldn't that depend on barrel twist? to fast a twist for a light round and the force just pulled the bullet apart. It probably happened with all three rounds who knows though I wasn't there.

I'll post additional details when/if they come into my Intel process.

Maybe he fired with his barrel still behind a barricade.?.

Quoted: ... or an old soft vortex but it hink they widened slowly over time. not with one shot.

Definately sounds like a Vortex FS issue (another reason to not like the open prong design).

Quoted: Quoted: ... or an old soft vortex but it hink they widened slowly over time. not with one shot. Definately sounds like a Vortex FS issue (another reason to not like the open prong design).

I was going to say that. I bet they ordered Vortex's from Bushmaster.

Quoted: Quoted: Quoted: ... or an old soft vortex but it hink they widened slowly over time. not with one shot. Definately sounds like a Vortex FS issue (another reason to not like the open prong design). I was going to say that. I bet they ordered Vortex's from Bushmaster.

Bushmaster sells Vortex's?  Don't see them on the website.  I need a few G6s.

I'm sure every nuke is different, but all the ARs on the site I work at (and every other nuke site I've been to) are pretty much plain jane 16" M4s with standard M4 oval handguards and A2 FHs.

I have seen something similar:
Officer qualifying with standard A-2 with standard FS.
Stage of fire was kneeling barricade.
Front of barrel was placed against barracade, officer did not notice due to sight height difference.
Officer fired one round that impacted barracade, due to proximity of barrel the flash suppressor seperated in many pieces.
No injuries, but the barracade had distinctive powder/flash pattern with parts of flash suppressor embedded into plywood braces on either side.  
Had there been another shooter in the next bay, they would have been peppered by fragments of the FS.

Edited to add:
Ammo was Q3131A 55 grn.

Quoted: Quoted: Quoted: ... or an old soft vortex but it hink they widened slowly over time. not with one shot. Definately sounds like a Vortex FS issue (another reason to not like the open prong design). I was going to say that. I bet they ordered Vortex's from Bushmaster.

+1

That might be why Bushmaster no longer carries the Vortex flash hiders.

The info indicates it failed destructively (no metal separated...) so I wonder if it was a Vortex or a conventional cage? "Officer clearly had muzzle through barrier when fired" so no dummy-induced obstruction.

Quien sabe?

No se`.

Hmmm, a 45 grain frangible projectile, probably fired from a 1/7 twist barrel?  Maybe it did come apart.

tagged ........

Quoted: If this is NOT a Vortex-related problem, I'd be VERY surprised.  It matches the known failure pattern exactly.  Nothing in this report indicates that the rifle was recently acquired, and it may well be that the officer in question replaced his A2 FS with the Vortex on his own. This simply doesn't sound like a failure that's possible with either an A2 or Phantom-type FS. -Troy

Troy-
Nuke security staff are VERY picky abouts mods. In addition, from what I can tell about this site (I'm an ex SecMgr nuke), this site rotates weapons. No 'personal' AR, as in 'give me rack # yadayada'. They generally have enough for the Contingency Plan (usually multiple shifts), plus spares. Not enough for 100% callout of ALL the shifts.

As soon as I find out, I'll LYK.


B-

I think more information is needed.

There needs to be an exact identification of the muzzle device in question. I find it interesting that it "peeled back in four separate directions." To me, this indicates there were four seperate tines, equidistant. If it was an A2, the solid bottom would be more likely to survive intact with the upper tines the weak point that would let go first, creating an asymetrical "peelback." An A1 would probably result in more than four sections peeled back. In addition, with the tines of these supported at the front, there should be more of a bursting effect or bulge with the front support section either gone altogether or still partially intact. Therefore I believe it is some type of aftermarket device, with four tines, probably unsupported at the end.

Also, with the 45 gr frangible bullets, it may indeed be a case of a too fast twist causing a failure of that lightweight bullet, due to centrifical force applied in excess of the design parameters of it. The bullet, coming "unglued" as it leaves the muzzle, COULD cause this type of failure.

I suspect a failure of a "Vortex" device, which HAS been known to happen, possible triggered by a frangible bullet coming apart, due to exceeding it's design parameters, or a flaw in that particular bullet.

But, being an "Armchair Commando," I could be full of it, quite easily.

Maybe we should try to get further information.



Lonny

Umm, wouldnt the model be XM-15?

Quoted: Hmmm, a 45 grain fragible projectile, probably fired from a 1/7 twist barrel?  Maybe it did come apart.

+1

tagged

This is scary.  Let's say that you were at your job or just an average joe that's at the range, and you aim at your target, pull the trigger, just to find out that the bullet blew out the suppressor and went side ways, injuring or even killing someone who you did not intend to hurt.

Question ... who's fault would this be?  Manufacturer for creating a defective product?  I don't see how this is the fault of the shooter AT ALL.

Please comment.

Quoted: Warrior-Poet, This is the first I've heard of this, I would like for you to give the name of the Nuclear Plant, who the guns were bought through, who sent the weapon in question into the factory, and your supervisors name. I look forward to your response to get all the information out in the open to the members of this forum.

This is why I love Bushmaster.  You guys are actually involved in the community and listen to our concerns!  :big thumbsup:

Ola BM!

The written report emanates from John Glatz at TMI. The site staff member to whom I spoke today  identifed the FH as a 4-prong 'Wirecutter' variant on Bushmaster rifles. I can only imagine this might be an earlier FH, as I can't recall seeing one like that on your site for a long time. They also indicated the event date was 29 September, and that they had contacted BM already, AND sent the weapon to you.

The person to whom I spoke also indicated that the FHs showed a high degree of FH internal erosion. When compared to typical USGI rack rifles, nuke rifles have been running a marathon since April 2003. Ours are 'common', so they get handed off every shift to the new force. We have more than one 'set', and can cover maintenance, training, and plus-ups of the Force. So, we're shooting ours alot, and I can see where erosion might cause abrading of the FH/Comp.

AR rifles have been in the nuclear fleets for at least 10y, when the first NRC orders required Security forces of Commercial nukes to have more than shotguns, EVEN IF state laws re: private security forces limited them to .357 caliber revolvers and 12g shotguns. Don't know how old their rifles are, and when asked he couldn't give a round count.

I do not work at TMI, BTW.

Quoted: Warrior-Poet, This is the first I've heard of this, I would like for you to give the name of the Nuclear Plant, who the guns were bought through, who sent the weapon in question into the factory, and your supervisors name. I look forward to your response to get all the information out in the open to the members of this forum.

Hey Jarrod, I know it may take awhile, but would you mind posting your (Bushmasters) findings after you examine the weapon?  

ANY possibility these are Vortex FHs?


Did BM sell complete rifles w/ the Vortex? This is the ONLY thing that comes close IMO.

Quoted: those are third gen (spiral cut) vortexs. if the one that blew up looks like that see my pic posted earlier in this thread.

From his description, that may be the case. No pics available at this time from TMI.

Did BM sell complete rifles w/ Vortex FHs? TMI insists this is as-delivered on all the rifles, and that inspections revealed others that had incipient failures/cracks/abrading.

EVERYONE gets sued. Trust me.

Bob

Quoted: This is scary.  Let's say that you were at your job or just an average joe that's at the range, and you aim at your target, pull the trigger, just to find out that the bullet blew out the suppressor and went side ways, injuring or even killing someone who you did not intend to hurt. Question ... who's fault would this be?  Manufacturer for creating a defective product?  I don't see how this is the fault of the shooter AT ALL. Please comment.

I deliver to a nuclear exclusion site about twice a week. I always look at ( admire ) their bushmasters with reflex sights. I have noticed how dirty the flash suppressors are on these weapons. It makes you wonder about the rest of the weapon. I do not know if that would affect performance.     Phil

That sounds like a DOE site.

TMI (and our) Security is in-house. I know our weapons get maintained by armorers (not parts changers). We don't let rifels come off a range and go in-service. They get cleaned and inspected. We have periodic rotations to ensure that the armorers get a close look at everything periodically.

Biggest issue: finish wear: like any MOUT/Urban Warfare weapon, they get a lot of handling and scuffing.