Hi Folks,

A forum member asked me if I would give some insight into how our M4's handle on the range because I've started threads on the AK's, pistols and .50 Barretts.

Here's a little background on what we do. We operate a high-volume range in Las Vegas. You can't bring your personal weapons in and rent lanes for an hour. Customers use only our weapons and our ammo. We only use factory new ammo and zero reloads. We keep maintenance log on EACH and every weapon to include cleanings, parts replaced and any other issues that need to be noted. We shoot approximately 400,000 rounds down range each month and the numbers have actually gone up a bit for May and June. Tourists get to shoot everything from Type 99 Arisaka's, M1 Garand C and D's, MP-44's, G43's, M2HB's, 240's, 249's, MG42's, MG34's, M-14's, Luger's, Swedish K's, M203's, M79's and you get the point. Some weapons are very rare historical weapons that rarely come out of collections or museums and see the light of day.

Here are some "facts" about OUR experience with M4's on the range.

- Some of our M4's have well over 200,000 rounds down range. Barrels have been replaced, gas tubes have been replaced, BCG's have been replaced but what sets it apart from the AK47's is that upper and lower receivers continue to function. AK's get to about the 100,000+ round count and rails on the receiver will start to crack. It's an easy fix with tig welding but they crack. We have yet to lose an upper or lower receiver from cracking.

- We get about 20,000 rounds out of bolts before we start experiencing issues. The headspace gauge will start getting closing on NO-GO but not close on field. We will lose a lug on the bolt. The bolt will start skipping over rounds in the magazine and fail to insert a round. We use LMT and Daniel Defense bolts and some will actually go longer but at about 20,000 rounds is when we will start to see issues appear.

- Gas tubes will erode away at the FSB after 12+ months

- Charging handles will "stretch" allowing the locking lever and spring to fly out

- Hammer pins and disconnectors on the 8.5" full-auto's will break after approximately 4,000-5,000 rounds regardless of the buffer weight

- We have yet to lose a single flash hider as compared to muzzle brakes on an AK-47. The muzzle brakes will literally split in half, looking a like bird with his beak open and go flying down range.

- We no longer use ANY piston conversions or factory pistons guns with the exception of the HK-416 "knock-off" TDI upper. I purchased a FACTORY brand-new MR556 and it started keyholing after only 10,000 rounds. I was SO pissed because I spent all that money on the gun and it couldn't last 10,000 rounds. I had barrels from before we even opened the range with 1,000's of rounds on them from J&T Distributing (chrome-lined) that didn't keyhole well into the 80,000-100,000 range. I don't know who makes or made the J&T barrels but I was so pissed that actually wasted the money on a MR556 and that's all I got from it. I purchased two of the 14.5" TDI knock-offs approximately 6-8 weeks ago and they have been on the line daily with ZERO issues. I only purchased them because people will come in specifically request the "416" and even they've never handled a weapon their entire lives, they KNOW that the top half isn't the "416 like in COD/MW".

- USGI mags have outlasted all of the other brands. We use UGSI (Brownell's with tan follower) and on a mag for mag basis, they have outlasted Pmags and a few of the other mags that we get from mfg'ers with new weapons. We don't have to worry about various generations with different weapons like the MR556, SCAR, F2000, Tavor or a couple of others that use AR15/M4 magazines.

- Cleaning bolts and carriers is such a pain in the ass as compared to our AK's, G36's, SCAR's, ACR's and most other platforms. We throw them in the ultrasonic cleaner filled with Simple Green (EPA, OSHA and disposal concerns for us) and they never full remove the carbon from the bolts. The armorers spend so much time cleaning them and keeping all the parts together as compared to most other platforms.

- The only piston system to last on the range so far is the HK416 and TD415 system. Ever other systems we have tried has failed in one way or another. I won't say who's broke or how they broke so PLEASE don't ask. Each mfg has their own system for cleaning intervals and we may not follow their way. We have a way of cleaning and keeping records that suits our needs because of so much use.

- There is company that has an AR system that has some "parts don't need lubrication" and that failed before the end of the first day. I don't think some mfg's understand that people REALLY use their weapons and when you're rocking full-auto all day they NEED lubrication. My armorers and RSO's were laughing when it seized it up because we knew there was NO way it would last on our range.

- The parts that we see break more often are the bolt cam, bolt lugs shearing off, firing pins and gas keys shearing off the bolt carrier.

These are just a few of the things that I can think of on the top of my head. Please feel free to ask questions and I will try to respond sooner than later depending on my schedule.

V/R
Ron

ps: I am sure there are some grammatical errors as I tend to read the words into a sentence that are not there. Some sort of dyslexia-type of issue that plagued me through eight years of college.

As the AK thread was, this is awesome!  I'll have to look you up in January.

Spectacular thread, thank you for all this information since your stuff actually gets used pretty hard from what you are describing.  In case you use silencers on the line, have you noticed that any types (or materials) of cans that seem to wear out quicker than others?  The more specific the info the better, but I understand that may or may not be possible.  Thanks again!

+1 Thank you

Have you ever considered trying a few LMT enhanced bolts?

Supposedly they've never heard of one breaking.

Might be the ticket for the heavy use you are putting the ARs through.

Just a thought.

BTW, great thread and great info, thank you!

for the record my PSA 12" loves wolf gold

Ron, sweet that the td416 rocks!

I need to go to the range with my 16" td

We use the following suppressors on the these weapons:

Surefire: Barrett .50BMG, M240, M249
AAC: M16/M4, Glock, Beretta,Walther P22, Sig Mosquito
Silencerco: FNP
YHM: M16/M4, Glock, Berreta, Walther P22, Sig Mosquito
Bowers: MAC-10, MAC-11 (.380)
TPM: MP5-SD

All of the cans have held up and each has suffered some sort of baffle strike from barely noticeable to extremely noticeable with the exception of the Barrett .50BMG suppressor. We don't use it that often but now that we have our upgraded M107A1 headed back from Barrett, it will start to be used on a regular basis.

V/R
Ron

Awesome information, thank you! By any chance, if you're able to say, have you tried using PWS brand rifles, and if so, how long did they last for?

Do you keep track of mrbs?

Fantastic thread; Colt or LMT BCG's are my favorite, and they are the only ones I use. I believe J&T/Doublestar barrels are made by ER Shaw, and have used a couple without problems

I just wanna jump on the kiss-ass band wagon and say I really appreciate the time you take to make these posts. You have a very unique insight into something we all love. Mucho gracias...

It's not feasible for us to keep track of MRBS because of the pace on the range. Also, it's not something that's really plays a big part of what we do. My RSO's are tasked with customer safety first and then customer satisfaction. They couldn't provide both of those and try and keep track of weapons jamming and take the info back to the armorers without the first two starting to lack. If a weapon jams once, there's a good chance it was user-related but a second jam means the customer gets a new weapon and they start all over with a fresh magazine, even if they got 24 out of 25 rounds down range. Most of the customers won't take the additional magazine because they feel guilty but it's worth the cost of the ammo to make sure leave with a huge grin and satisfied.

V/R
Ron

That is just good customer service.

I wish all companies were as good.

best

mqqn

Just wanted to take the time to thank you for chiming in on your experiences, it is definitely appreciated. I will echo what others have said and would like to see you add a few offerings from Knights Armament to your inventory. The SR25 series, in my opinion, are one of the best semi auto gas guns available but, I would definitely like to see how their SR16 series hold up compared to the others you current have in rotation.

Keep the information coming, you for sure have a captive audience.

Thanks for posting the information.

Since you actually do shoot so much through the rifles, I am curious just how well the CHF "machine gun steel" barrels with heavy chrome lining hold up. Granted, you mentioned that you are only shooting for close range, but it would be interesting to see just how much more these barrels hold their accuracy over other barrels.

I have some of these CHF barrels, and I like them just fine, but I'll never be able to put tens of thousands of rounds through mine!

Was waiting for this after seeing the AK thread. Thank you for sharing.

Tag

Great insight.

Another +1 from me on seeing SR16 and E3 bolt performance.

Besides magpul and USGI, what other brands of mags do you use, and how have they done?

In your experience, how did chf barrels perform compared to button rifled barrels, as far as reliability, longevity is concerned.  Does chf really out last button rifled barrels?

Thanks for the info.

How do you deal with usgi mags that get dropped fully loaded and bend feed lips?  Any reliability issues after being bent back into shape?

Brownell's tan follower mags don't deform from mild drops onto concrete.  Check out the test I did.

https://www.ar15.com/archive/topic.html?b=3&f=17&t=610837

The info in this thread is amazing!!!!  I hope it keeps coming!

Yes thanks very much! Good read!

Great info.  Thanks!

I will get some of your questions answered when I get back in town. Don't think I'm ignoring you guys.

V/R
Ron

Holy crap this post is awesome. Thank you very much for sharing the info!

Mods, can we sticky this just because it's that awesome?

Acutally, you have been quite helpful.

Please forgive the enthusiasm.  This is the "Holy Grail" of non-anecdotal data that is being collected.  You are answering a lot of questions with no bias besides what works for you business.  CHF vs Standard cmv barrels, lube options, maintenance routines, magazine options, common part failure, round count are all things, until now, were explained anecdotally.  Thank you for taking the time from your business to answer our questions.

I haven't read anything stated by the OP that I would say "clearly" one outlasts the other. Other than the "one" HF MR556 barrel only lasted 10k rounds.

I might have missed one, but below is what I gathered the OP stated about barrels.

 

I stand by the standard vs HF barrel life are about equal. Nothing to back up this claim, but I have yet to see anything that "proves" HF last longer.

Perhaps the OP has the best evidence to date on this...

Fantastic thread, thank you.

Best Thread Evah!

There's a lot of info here, some of it surprising.  To summarize the various replys so far from the OP:

- Brownell's GI mags outlast PMags.  They outlast everything in fact.  That, I would not have expected.
- With some possible exceptions, piston AR's don't hold up.  Again, not something I would have expected.  I personally always thought they were a gimmick, but didn't think any but the crudest renditions would fail any faster than DI.
- Changing handles fail.  Again, unexpected.  I just figured it's a near static piece that would last basically forever.
- No comment on extractors.  I would have thought those would fail faster than the cam pin or lugs.  That said, perhaps an oversite to mention by HndersonDefense, or possibly they are considered consumables and just not even worth noting?  
- Apparently Bolt's and BCG's aren't all the same after all (a common mantra here). DD and LMT bolts hold up better than all others.  
- Good barrels are lasting much much longer than the ~25,000 round expectation (though not clear what the round count actually is).  That's incredible.  These are full auto guns.  That has got to be wearing out BBL's way faster than more normal semi-auto fire (heat).  Details aren't completely clear, but it's sounding like hammer forged barrels hold up better(?). A barrel is considered a crappy BBL if it only lasts 10k rounds.
- Short barrel rifles have much faster throat erosion.  I don't know why, you'd think they'd be under less heat for a shorter period of time.  At a guess, maybe it's because the early pressure release (bullet exits sooner), allows the chamber contents of hot and large kernels of still-burning powder to eject down the barrel.  Just a guess.
-

Thanks for giving insight into your side of the industry. I find it fascinating and informative to learn about the "behind the scenes" stuff in any industry.

What do you do with all of your brass? Is it even worth your time to sell it other than for scrap metal prices?

Why is this?

I was referring to the future collection of data where he said he would keep us posted.  This COULD tell us more about barrel longevity  in regards to the manufacture process.

tag

I keep telling you guys, it's not the process that leads to barrel longevity so much as the steel.  The engineer at FN specifically stated that it is FN's propriety blend of steel ("machine gun steel") that leads to such a long life in their CHF M249 barrels.  They also use a different type of chrome that plates on thicker than that used in the bores of the M4s.

This is our first "vacation" (just a quick, two-day drive to the beach) since we opened the range and I promised the wife no business so I'll make it quick with a few points.

- we do lose extractors and even lost the extractor on the HK. I don't blame them because we have had extractors break at early round counts and high round counts from the same mfr's.

- we've used CHF barrels alongside standard chrome-lined barrels (LMT, J&T, Green Mountain) and though I don't have a true round count, they were put online at about the same time with the same amount of use and one didn't do "better" than the other. Remember, my only concern for accuracy is that it can hit the red center of a target at 15 yards.

V/R
Ron

When using BCG's manufactured by other than DD or LMT what failures did you see. You have mentioned failures of individual bolt components such as cam pins, bolt lugs etc. Other than the shearing of gas key screws(you mentioned gas tube shearing off) what can fail on the bolt carrier itself? I would think these would last indefinitely.



Keep the real world experience coming. It is pretty rare to get this type of info on high round count rifles and parts.

This is sig line material, at the very minimum just to quick reference everytime the question comes up which is almost daily.

I'd like to see data from 50 yards +
Kind of hard to judge loss of accuracy from 15 yards.

Great thread. Thanks for the write up.

No reason to get a full SR-16 when all you'd need is an upper.

Their SR-15 buffer is 3oz just like a standard carbine buffer.  The spring is also standard carbine fodder.

Great info, thank you for sharing.

It's amusing to see all the KAC fanboys come out of the woodwork nervously looking and hoping to find validation!  

He stated in his high round count pistol thread the following about Federal and why they use Magtech instead :

This is where the lucky-gunner data comes in handy.  While there was some slight accuracy degradation (at 50 yards), it held pretty good until the keyholing started.  In their case, somewhere between 4000-6000 rounds, with Wolf Steel (steel jacketed bullets).  They never hit it with the brass jacketed bullets during those LuckyGunner tests (though did see velocity decline).   Note Henderson Defense is not using cheaper steel cased ammo - for fairly obvious reasons I imagine.

No kidding.

Nothing has been said that takes anything away from the CHF debate. 15 yard accuracy? Lol.

You guys really need to read up on all the LMG testing that was done. CHF was found to be insanely more durable. Not apples to apples comparing LMGs to semi auto ARs, but more durable is more durable.

Thing is, I'm tired of getting sucked back into this rehash anyway. Frankly, it is literally the exact same four people who speak out against CHF having any benefits. Every time. Just the same four people. Though droves of people speak out in contrast to that small group of four - that includes engineers and machinists as well. At this point, we should probably just let those four live in their bubble.

Who looks nervous?

I simply see people saying that it'd be cool if he had an SR-16 to rent out and abuse as well...