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View Full Version : M-16 QUESTION FOR YOU G.I.'S IN HERE:


supersonic
04-16-2009, 8:05 AM
This is something I've often wondered about, but obviously never been able to find a decent answer to. How long / how many rounds of 5.56 does it take (in F/A, of course) to fry a BBL? (I know this isn't an exact science, so I'm asking in terms of "approximately"). Anyway, I am just very curious any response(s) would be very cool.:cool:

spareparts
04-16-2009, 8:12 AM
I can't tell you about the M16, but on a live fire excercise I put 400 rounds through an already hot barrel in my M249 SAW in two 200 round bursts. The barrel got cherry red and the plastic on the heat shield melted but afterwards it was still servicable.

PatriotnMore
04-16-2009, 8:19 AM
I can't tell you about the M16, but on a live fire excercise I put 400 rounds through an already hot barrel in my M249 SAW in two 200 round bursts. The barrel got cherry red and the plastic on the heat shield melted but afterwards it was still servicable.

Not to hijack the thread, one quick question, any chance a round could/would cook off in the chamber from being that hot?

kingjoey
04-16-2009, 8:41 AM
Not to hijack the thread, one quick question, any chance a round could/would cook off in the chamber from being that hot?

No, the M249 is open-bolt, there isn't a round in the chamber until you pull the trigger

mooster
04-16-2009, 8:50 AM
I'm not military but I stayed at a Holiday Inn Express once. (I do work on Army vehicles and weapons though)

Could you define "fry a barrel"? As a barrel heats up from sustained fire you start to incur permanent damage to surfaces and structure. You could fire till a barrel turns red hot, but as the previous poster stated the barrel is still usable for shooting. Point of impact and dispersion could change.

Also, consider that it is not only # of rounds that matter but rate of fire as well. Breaks in firing have a significant effect on cooling and wear.

supersonic
04-16-2009, 11:01 AM
Could you define "fry a barrel"?
Also, consider that it is not only # of rounds that matter but rate of fire as well. Breaks in firing have a significant effect on cooling and wear.

"Fry a barrel" as in "end its service life" ; "complete erosion of throat" ; "wear out the rifling" ; "wear out the barrel" ; etc. Take your pick. Also, I did reference both # of rounds and ROF ("time") in my OP.

mk19
04-16-2009, 12:40 PM
Impossible. Since since m16a2's and up don't have F/A. We tried shooting some with 1000s of rounds as fast as we could our hands would burn even with leather gloves on and nothing was happening to the barrel.

technique
04-16-2009, 12:48 PM
Not to hijack the thread, one quick question, any chance a round could/would cook off in the chamber from being that hot?

in a class I took we briefly went over something along these lines...

After a buttload of shooting and your barrel is super hot these guys recommended that you drop the mag, empty the chamber and reinsert the mag.

They said, excessive heat would cause the round to swell in the chamber. Not causing it to cook off, but causing a failure when you attempted to fire again...like a FTE, blow out a primer, Jam of some sort, that type of thing.

Technical Ted
04-16-2009, 12:48 PM
I have a document in PDF form from the US Army somewhere that indicates that an M4 carbine barrel will fail after approx. 400 rounds, full auto with the only pauses being changing 30 rd mags.

Correction: 400 is wrong. See image in next post.

I'll try to relocate it and post it somewhere.

http://www.hunt101.com/data/500/medium/9184AMSTA_AR_ES_92_2.jpg

Technical Ted
04-16-2009, 12:52 PM
Someone has it online:
http://www.google.com/url?sa=t&source=web&ct=res&cd=2&url=http%3A%2F%2Fstinet.dtic.mil%2Fcgi-bin%2FGetTRDoc%3FAD%3DADA317929%26Location%3DU2%26 doc%3DGetTRDoc.pdf&ei=HIznSZfjI5PqtQP7z6DmAQ&usg=AFQjCNGTPDjp5w9j_Q_HhUiitf_rle2i0A&sig2=OKrDyDPT3AwZnrhHpj10Dg

http://www.hunt101.com/data/500/medium/Fire_to_Destruct.jpg

spareparts
04-16-2009, 1:30 PM
Someone has it online:
http://www.google.com/url?sa=t&source=web&ct=res&cd=2&url=http%3A%2F%2Fstinet.dtic.mil%2Fcgi-bin%2FGetTRDoc%3FAD%3DADA317929%26Location%3DU2%26 doc%3DGetTRDoc.pdf&ei=HIznSZfjI5PqtQP7z6DmAQ&usg=AFQjCNGTPDjp5w9j_Q_HhUiitf_rle2i0A&sig2=OKrDyDPT3AwZnrhHpj10Dg

http://www.hunt101.com/data/500/medium/Fire_to_Destruct.jpg



So how close to destruction do you think my SAW was?

buffybuster
04-16-2009, 1:40 PM
The gastube will fail before the barrel bursts. Somewhere around 500 rounds cyclic.

This is WAY BEYOND the design parameters of this weapons system.

technique
04-16-2009, 1:49 PM
Not sustained FA or destruction of a barrel, been seen before but always a good vid...

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/u5CQOvdYW6c&hl=en&fs=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/u5CQOvdYW6c&hl=en&fs=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

CaptMike
04-16-2009, 11:16 PM
this is a cool video of the M60.


http://www.youtube.com/watch?v=dGAwrmOapb4 (http://http://www.youtube.com/watch?v=dGAwrmOapb4)

gtmmark
04-16-2009, 11:25 PM
I once got a M60E3 barrel so hot that it drooped, I also blew the gas regulator off of a M240 after a nice 100rd. burst.

docsmileyface
04-17-2009, 12:46 AM
****, me and Stormfeather might just have deadlined a couple barrels at the range then yesterday..... :43:

reidnez
04-17-2009, 10:46 AM
Someone has it online:
http://www.google.com/url?sa=t&source=web&ct=res&cd=2&url=http%3A%2F%2Fstinet.dtic.mil%2Fcgi-bin%2FGetTRDoc%3FAD%3DADA317929%26Location%3DU2%26 doc%3DGetTRDoc.pdf&ei=HIznSZfjI5PqtQP7z6DmAQ&usg=AFQjCNGTPDjp5w9j_Q_HhUiitf_rle2i0A&sig2=OKrDyDPT3AwZnrhHpj10Dg

http://www.hunt101.com/data/500/medium/Fire_to_Destruct.jpg

Wow, I would love to see some video of this. Even better, I want these guys' jobs. A 1700F barrel rupturing! That has to be quite a spectacle. I'm curious as to why the M4 holds up better than the M16, though. I would expect the M16 to be equal or slightly better, since there is more barrel mass to absorb the heat.

supersonic
04-17-2009, 10:50 AM
Someone has it online:
http://www.google.com/url?sa=t&source=web&ct=res&cd=2&url=http%3A%2F%2Fstinet.dtic.mil%2Fcgi-bin%2FGetTRDoc%3FAD%3DADA317929%26Location%3DU2%26 doc%3DGetTRDoc.pdf&ei=HIznSZfjI5PqtQP7z6DmAQ&usg=AFQjCNGTPDjp5w9j_Q_HhUiitf_rle2i0A&sig2=OKrDyDPT3AwZnrhHpj10Dg

http://www.hunt101.com/data/500/medium/Fire_to_Destruct.jpg

WOW, thanks TT. That report is VERY interesting, indeed. It really gives you some graphic "visual & audible" insight as to how a F/A weapon "acts" right before it self-destructs. The parts I found compelling were : "muzzle flash increase/noticeable drooping of BBL at muzzle/muzzle report (sound of weapon firing) "changed" --- all about 30 seconds (or was it rounds?) before destruction occurred! Neat S**T!!!!!!:thumbsup: