M4 barrel fell off
“FREEFALLE7″, a Ranger Instructor, posted the above photo at AR15.com. A student, on arrival at the Swamp phase of Ranger School, showed him his M4 and said “my barrel fell off”. His punishment for not telling an instructor at the Mountain phase (the previous phase) about the broken M4 was to be given a M240, which weights 27 lbs, as a replacement.
Keith J came up with a plausible theory of how this happened
Salt water in the threads. Steel rusts. Steel in contact with aluminum. Aluminum then oxidizes, reducing the rust to iron dust. Joint remains tight until it is abused, then it just falls apart.
This all started when the barrel was installed and it was tightened a bit too much, causing the anodizing to crack
Of course this would have happened over a long period of time and use.
Thanks to Jay for the link.
“His punishment for not letting an instructor at the Mountain phase was to be given an M240 to carrying around instead of his carbine.”
Didn’t quite understand this part… Rephrase?
Crystal, lol, that teaches me not to forget to proof read. I hope is is clearer now.
bad, bad memories…….
“troop, you know what you and an aluminum can have in common? you can both be recycled!”….arghhhhh!
Holy full-auto, Batman! That’s one symptom of some serious, sustained, full-auto fire! And more than once! He’s lucky he wasn’t firing that thing when it gave way!
The only logical reason I ever heard for the military’s adoption of three-round burst was that it would slightly decrease the rate of fire when using the newer 30 round magazines. Apparently, the M-16A1 had a tendency to launch their barrels when sustained FA was used in training, with total disregard for the amount of heat that was going into the receiver. There’s no amount of training that can counter a reckless disregard for safety, and firing a rifle until the barrel is cherry-red is something I’ve seen and heard about people doing on more than one occasion. Respect your guns people!
Keith J know his stuff. Another thing I would like to point out is that the armorer probably forgotten to grease the threads.
Not being a military person familiar with the practices of military armorers, I have to ask – what is there in place to protect a solider from having this happen to his combat weapon?
And since there is often such rousing discussion re: weapon failures on this blog, what kinds of horrible consequences could there have been if the rifle had come apart this way during firing?
I’m thinking unsupported chamber explosion and a wild shot.
If I had to guess, I’d guess that the barrel nut wasn’t torqued down properly and so worked itself loose through vibration and heating/cooling cycles.
Weird question I’ve had for a long time: Anyone make a steel upper for the AR? I know that there’s basically zero point for having one made out of steel rather than aluminum but I just thought it’d be neat.
Dom, it is up to the solider to make sure his/her equipments works.
These weapons are not safe queen. They are used and abused regularly by kids. Not only that these weapons are suppose to last forever. They are repair or retrofit at the armory level. There are some first generation A1 lowers and uppers that are still being use by our military.
The gas tube prevent the barrel nut from twisting/working it way lose.
One more reason to switch to AK
Yet one more reason why Armalites=epic fail
I’m amazed that this isn’t a regular occurrence, aluminum threads with steel nut requires a very carefully torque to get both good connection and no damaged threads. If you add aluminum-typical fatigue and creep, you can probably see this even in weapons that were always handled according to specs. With this weapon obviously in a training unit and subject to both heavy firing and rough handling (after all, the trainee knows he’s getting rid of it at the end of his class, and he doesn’t have to rely on it in combat) it looks like they got a lot of use from this upper. Would be interesting to find out when it was made.
AK, give me a break. If you think those rifles doesn’t have their own set of problems I got a bridge to sell you in NYC.
The upper probably got rebarreled many times. The upper as well as the lower receiver should last forever. The problem was over torqued and most likely the armorer didn’t grease the threads to prevent corrosion.
You want a break? Sit down and enjoy
Everything and anything has some problems, but compare to M/AR rifles AK looks pretty good. It is so sad that our guys still has to do there job with weapons which might be more dangerous for operator then for target.
You have no idea what you’re talking about. Go back and play your video games. Let the grown up do their stuff.
“He’s lucky he wasn’t firing that thing when it gave way!”
I don’t think the consequences would be as bad as you think. The bolt would be locked into it during firing, and the tube stopping rotation… actually, and I’d have to look at one real closely, in battery it’d be hard to impossible to launch the barrel, some friction point in the loading/bolt return phase would have to shove it off.
At that point, with the barrel going/gone, the front of the reciever is open. I don’t think you’d have enough instant pressure do get frags or gas anywhere but out the front and out the ejection port. Then again, the cartridge would be hanging halfway out the front of the reciever… but then AGAIN, that also means it has no cross-axis reference, the ejector would toss it off to the side before the firing pin could strike it. THEN again, if the ejector’s not working right if could be held to the bolt face tight enough to fire… but THEN AGAIN (heh) the gun would have tied up before the failure point.
Look at the photo, the threads on the reciever are noticeable flattened. I bet the barrel nut was corroded (as above) and/or was out of spec and overtightened at some point, predamaging the threads to where they stripped later.
It’d take some force still to strip those threads off… I’d LOVE to know at exactly what point in training it broke loose. You can’t apply side force to the barrel nut because the chamber extension is tight in the receiver… you can’t push on it for the same reason. It’s have to be pulled, or have some action applied that yanked the barrel straight off.
Do they still use bullet traps or blanks in simulated fire training, or is it all IR now?
You know, the above thoughtline is why I respect the AR15 platform. There’s a hell of a lot of engineering that went into that gun to make is as simple and “foolproof” (engineering wise) as possible.
I was considering the same the other day on different bounds, and the only things I could come up with as improvements were a different mounting method for the stock tube (no big-arse threads, interference pins, I’m mentioned this before), a directly-attached “post” operating handle instead of the one-way top mount it has now (though, would really slow the lefties down), and modular/replaceable drop-in fire control assemblies, like Chip Mc makes but containing the FA sear or 3-shot cam.
Since I’ve never seen some of the above, I guess that’s two patent-disqualifying posts of the day…
My guess would be that the weapon had been rebarreled several times. Its also possible some Gung Ho troop went a little further then he should have in disassembly for cleaning. As a unit armorer I had to repair several M-16’s that people took apart when they should not have.
I love the M-16/AR-15 platform. Anyone who visits my house will see that. I built my first AR in 1988. When the kit arrived, nothing was assembled, I repeat, NOTHING. The instructions warned that barrel torque was critical. Everything since has come with the upper assembled. Manufacturers are doing this to eliminate risk from people who don’t torque it right.
Cleaning the chamber is much easier with out a pesky upper in the way, but I’ll be darned if I’m gonna do it that way.
jdun1911, nicely said. Not everybody here around is a little kid. I do have some kind of limited experience with m16/Ar15 platform. I served with SVD. We study M-rifles and it is wonderful, over-engineered rifle. Very pleasant to shoot at shooting range. Complicated enough that it require an specialist to do half of the adjustments, several day of training for soldier to clean and extremely dangerous to perform full maintenance at the field. American pride and political games preventing soldiers from getting a good weapons which plenty around.
Give M-rifle to police and SWATs, give soldiers combat weapon.