I've owned no less than 7 sr15s in the past few years, but this looks really bad.  It did worse than aero uppers lol.

Yikes.

we did that one yesterday. the DD beat it slightly.

https://www.ar15.com/forums/General/DD-and-KAC-Rifles-Catastrophic-Failure-Videos-exploding-barrels/5-2693610/

I’m not even surprised. The Mod2 barrel is thin so that result is as expected.

However that doesn’t mean it’s bad. In my whole 6 years in USMC Infantry I have never been in a situation where I have to fire my M16A4 or M4A1 on cyclic like that. We have belt feds for that purpose and even with those we don’t run them on cyclic like in these torture tests.

I can personally tell you those 14.5” Mod2 barrel is exceptionally accurate tho for being chrome lined. I’ve shot a 1.75” 3-shot group at 500m using Mk262 Mod1 with one.

Not a particularly novel discovery due to the barrel profile imo. I think what makes KAC special is the gas system and bolt. The barrel profile is what it is. Meltdowns are entertaining, but I don’t think they’re a very practical test lol. Almost nobody is going to take their duty/civ owned Aero or Geissele or KAC or Colt or whatever and put 30 mags through it at a sustained rate of fire. Those very few who may potentially need to do that one day have air support and belt fed machine guns to back them up - and even then, I don’t think they’re sitting in a defense with 30 mags at the ready. Lets not kid ourselves lol.

Regardless, fun video. I’m glad someone did it for the sake of conversation and entertainment.

I can understand the entertainment value or those looking to find the weakest link in a raw stress test… but I think ‘horrible results’ is a stretch when you consider the purpose behind the machine.

For example: LMG’s, which have significantly heavier barrels, call for a barrel change every 400rds of normal operation (burst cadences) or 200rds of sustained fire.

The actionable insight that I glean from the video is that the barrel would benefit from a heavier profile if your course of fire calls for extreme sustained volume. In doing so the overall weight of the platform increases and then other (and arguably more significant) aspects suffer; like mobility and portability. You’d probably be better off with a different tool for the job.

I'm critical of KAC, but no 5.56 AR survives sustained fire like that. Nor would anyone have any reason to shoot like that.

You would have to run this test with a minimum of ten rifles to get any meaningful data. Also you need to be consistent in mag sizes. Running a d60 does more damage than running two thirty rounders.

I posted in the other thread but the most impressive melt down I ever saw was the Stern 9mm AR which ran over 6000 rounds full auto, and still worked. Iraqveteran video.

Exactly my thoughts.   My SR-15 is almost as accurate as a "match grade" barrel that I have, but the KAC is more reliable.

This is pure 'guntuber' clickbait nonsense, regardless of what brand is undergoing this rigorous 'testing.'

You're using a weapon in a manner in which it wasn't designed under conditions that aren't realistic. Oh no, something broke. I'm shocked. Now I must go to Reddit and proclaim how 'brand X' is better because it lasts a few rounds longer than another brand in a Youtube video!

100%. You took the words right out of my keyboard.

In terms of value, this is right in line with watching a Jerry Springer fight. Mildly entertaining for the 30 seconds in around when the barrel explodes, but zero influence on my life choices.

Entertaining but not surprising. Catastrophic failure is only second to the "wooooos!" like @ 4 mins 25 seconds. Cracks me up.

Anyone conducting a "meltdown" of a rifle either has no real experience & knowledge, or they're doing it for the jackass clicks. Either way, they've told you exactly who they are, and they should be ignored. A rifle isn't a belt fed machine gun. Belt fed machine guns have quick change barrels, or are liquid cooled for a reason.

You expect a pencil barrel to perform like an LMG?

If your goin into a war zone with 16 mags or 500 round strapped on you God bless your hulkness.

I really like the profile of the  kac barrels , bcm elw , and criterion core barrels.

Exactly what i said ^

MAC-V-SOG are known to have carried a ridiculous amount of ammo and I think were approaching this number on LRRP missions in Laos and Cambodia.

99.9999% of people here are “not that guy.” Lol

Yes, the SOG guys would carry 500 rounds. However they wouldn't shoot it on full auto continuously until it was gone. That's just dumb. The ammo you carry is life; once it's gone you're screwed.

Don't do that to your gun.


Problem fucking solved.

G36 went 900 rounds until it was literally on fire. They put it out and run another 30 rounds through it flawlessly. This was filmed at HK Oberndorf.

I'm a lover of KAC as I said, essentially 2/3rds of my collection are knights rifles.  But the takeaway is its performance relative to other guns.  I know its dumb, and basically pointless, but that doesn't change the fact that a lot of budget rifles did better.

I wouldn't know since i havent watched the other ones - but again, this is not a surprising discovery assuming those other rifles have thicker barrel profiles. If they ran that long with the same or similar barrel profile (the geissele being one probably) then theres some logic to this - even though it is an unrealistic and pointless test.

“The Ferrari F40 was only able to run at redline on the dyno in second gear for 5 minutes, but the Honda Civic was able to do it for 10 minutes and it is therefore better” sounds like a silly argument because it doesn't replicate anything. This really isnt any different than what some are saying after watching this video.

Firing full auto as fast as you can swap magazines with an AR-type rifle is really a test of the barrel and gas tube, as that's where the heat goes.
We use a thin, nearly pencil profile on 16", 14.5", and 11.5" barrels as they meet the requirements of use with the lowest amount of weight.
The less steel in the barrel, the less thermal mass to hold the heat being put in, the faster the temperature rises and therefore the faster the yield temperature of the steel is reached.
The best performing rifle in this abuse case would feature the thickest barrel possible made of a decent CHF steel.

In many rifles the gas tube will go before the barrel, for the simple reason of them reaching their failure point before the barrel does. Bent gas tubes will show greater temperatures at the bend, as the hot pressurized propellent gas will hit that bend and transfer heat there.

Precisely zero carbine acquisitions programs require full-auto fire of greater than a basic load (6-8 magazines) without cooling, as it's simply grossly outside of the use case for the item.
It's roughly equivalent to ranking new vehicle models by how long they will hold 8k RPM with the coolant drained.

Melt down demos are nothing than ballistic masturbation

There are some russian vids floating around of AKs and the same thing happens.  Imagine that.

"Horrible results"

You're right, because so many civilians have a select fire lower and 1,000,000,000 mags lined up ready to dump into the dirt.

GTFO.

Useless test

Meh.

I've seen and worked on a bunch of MOD2 guns that were used operationally in extremely shitty environments, rode hard and put away wet, that did just fine, ran like typwriters, killed plenty of bad guys, and then came to an inglorious end when the group decided to change to the next new "cool guy" system that came down the line.

This "test" is dumb. Even the most hard charging, high tier dudes making the worlds worst bad guys take the room temp challenge quite simply don't subject their weapons to that kind of firing schedule because it is ineffective in the real world.

These dumbass videos exist for clicks alone.

Muh bolt. Muh gas system.

Both of which are best in class. This test did nothing to show otherwise

I have owned plenty of SR15s to know they are overhyped. I’d rather take a LMT over a SR15 and even a Geissele SuperDuty with the REBCG.

10 years ago KAC was the leader in the Stoner rifle design. But others have caught up and surpassed them.

KAC fanbois rationalizing this meltdown test:

Damn I guess thats why the UK adopted KAC over all the other options

Call me stupid for asking this, but……..

Just what is a 500 round full auto melt down supposed to prove?
In what real world or military setting purpose would this take place?
I can kinda  understand the “mud tests” but this melt down crap?

Yes and No, I think the super duty is probably one of the best systems going for the price and what you get in return. I have found the g barrels are very accurate.  I have not seen anything long term on the REBCG but i own several so we shall see.  Lmt quick barrel change and rigid rail are the main selling points for LMT, the 556 barrels are heavier than they need to be. Their 308 rifles feel over gassed as hell and are fairly hefty.  The knights sr25 apc was the best shooting 308 semi I have shot.  

My knights mod2 14.5 is one of the smoothest shooting rifles I own.

I was recently issued a KS-3 with their new can and that rifle really impressed me.  

I hear what your saying and theres alot of solid brands but I still think knights is one of the most innovative.  

This meltdown is pure click bait and entertainment.

If the results of this video are beyond your ability to understand and have caused you worry, you probably aren't smart enough to be around firearms in the first place.

While I agree LMT and G are doing neat things with the AR platform, I'd really love to hear how you quantify other brands surpassing them.  KAC bolts don't break, and they just made them even better with the 3.2.

Until they start breaking, I'm not sure how anyone could do "better", because...well, how else would you quantify performance?

I do agree that G and LMT are outstanding platforms, and some may find less proprietary parts appealing, or cost.  Can't argue that, but I'm having trouble seeing how they have surpassed KAC.  Come close or equal to in *some* aspects?  Perhaps.

endurance of a weapon when severely abused.

Nobody ever drives their daily driver around at it's top speed, goes a 1/4mi balls out, races around town anything like the Nürburgring, or needs to do tractor-pulls with their trucks.  They're over-the-top abusive tests designed to strain a vehicle to it's limits.  People test machines at their absolute limits because in many instances numerous brands of the same thing perform their function equally effectively under normal operating conditions - so equally that determining "the better" one is impossible to discern.  Even the military has weapon trials where they put guns through rigors not typically encountered.  Most middling AR15's in 2023 are well suited to casual and even typical combat firing schedules that they could easily be relied upon.  Coatings and tolerances are advanced and controlled enough that weapons can be neglected without seriously impacting reliability.  Mid tier ARs can hit 1MOA or near to it with consistency and good ammo.  So how do you quantify the superior capabilities of something "High end" or "Tier 1" from the rest of the pack?  If they can't be quantified by some sort of controlled test, even if beyond the scope of normal operations... Do they actually exist?  Or are they just a manifestation by owner's who paid a premium to justify their purchase?

Pics? Review?

I promise I will get something up for you guys, next team range day is Jan.  Wanted to get several hundred through it but initial impressions so far is that it runs great.  The suppressor surprised me in a good way.  I dont want to get to ahead of myself, in a few weeks I will get something up.

For a real competitive acquisition program participants are provided a requirements document that lists required and optimal performance and physical traits.
Bidders send in their responses to the requirements documents along with bid samples for testing.
As with all things, there is trade space on those requirements, and for a directly applicable example as it related to barrel profile: endurance/durability/strength of design performance testing based on the requirements will be done, accuracy/dispersion testing based on the requirements will be done, and some kind of environmental testing will be done. Along with those kind of performance requirements, physical characteristics such as weight, barrel length, and overall length will drive the bidder to decide where to focus effort. If, for example, a performance requirement stated that the endurance test would be back to back full auto fire until failure, with the best performer being selected regardless of all other factors, or ranked by that test with weighting toward that test, I would submit the thickest barrel I could with as many cooling features as possible. Here are some open source P-specs that give a decent reference:
http://everyspec.com/MIL-SPECS/MIL-SPECS-MIL-DTL/MIL-DTL-71186A_30742/
http://everyspec.com/MIL-PRF/MIL-PRF-030000-79999/MIL-PRF-32316_AMENDMENT-1_25025/

As it is though, most tenders will value reduction of burden to the user, which means less weight. When it comes to small arms, reduction of barrel weight via profile is the fastest way to reduce weight. Take a look at the Colt 6720, that lightweight barrel does everything the 6920 barrel will do, but will heat up faster. Why would Colt ever do such a light barrel profile? Weight. If dropping 0.5lbs would put a submission into an "O" (objective rather than threshold), that will give them a competitive advantage. The consumer-side desire for light rifles has pushed industry to provide lighter barrel profiles than heavy full-auto fire would require. The KAC SR-15 Mod 2 Carbine is no different in that regard. It is a very high quality barrel steel with a proven life of well over 20,000 rounds, but the light profile puts it at a disadvantage under an extreme heat-management "test".

There are absolutely quantifiable test methodologies for firearm performance and selection criteria, just like there are for any other item.
Here are some open source test protocols:
http://everyspec.com/ARMY/Test-Operations-Procedure/TOP-3-2-045_32068/
https://apps.dtic.mil/sti/citations/ADA587409#:~:text=This%20TOP%20contains%20a%20compilation,weapons%20up%20to%2050%20mm.
https://apps.dtic.mil/sti/tr/pdf/ADA156982.pdf
https://apps.dtic.mil/sti/tr/pdf/AD1070714.pdf
You can also dig into STANAG and DEF STAN protocols.

Good info, I’ll keep this testing and your opinion in mind next time I’m shopping for a light support weapon/automatic rifle.


Oh, wait. This is a meaningless “test” with no practical application.

I don’t care and highly doubt KAC does, either.

G has too many QC issues for me to consider them.

LMT does pretty well most of the time.

We so need a LIKE button……

Part useless test grounded by a lighter barrel profile, part truth being out performed by 1/3-1/6 cost alternatives. Maybe KAC should stop cheaping out and go back to thicker dimpled barrel profile or flute it.

I think LMT has outpaced KAC in large frame AR’s. The versatility of their barrel change system and consistently accurate barrels (all 4 of mine shoot better than my EMC ever could have dreamed of) are major points to consider. The SR-15 is a different animal and Instill think they’re really hard to beat for a lightweight multi-use carbine. That’s also being said at or below their MSRP price point. When people went full retard through COVID they just weren’t worth the squeeze. Just my opinion.

Its funny but I feel the exact opposite. I really like the SR-15 ambi platforms alot but there are dozens of other options that can do the same thing at different (and mostly much lower) price points, including stuff you just put together with good quality parts.  The SR25 on the other hand is still to me the standard by which all others are judged.

I do agree that pricing is through the roof but that happened across the board for many things.  Try to buy a MR or AA import factory Galil, anything for the legacy HK 9x series like lowers / trigger packs, bolts/carriers or stocks, anything factory 416 etc. -  prices are still crazy and I dont expect will be coming down unless we continue the downward trend in the economy for a lot longer.

I haven't played with an LMT large frame yet, how is the weight on them?

My only SR25 right now is a 6.5cm.  I have zero complaints about it, but really don't have a whole lot to compare it to.

I will wholeheartedly agree with this. The COVID pricing was silly. At or below MRSP? Hard to beat an SR15.

That's what Ben Webb is trying to justify on his FB. Going full retard will tell how great the product destruction equates to poor quality.

Even with Iraqivet8888 destruction videos some are just to draw in the numbers. At least, he tries to bring in some fairness with replicating the same mags use in sequence.

I can't believe how many people here don't understand why the SR-15 performed the way it did in this supposed "test".