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.

IMO it's time for another revenue stream for these guys. Bring on a lackey...errr...intern and have them spend about half their time doing detailed tracking of failures etc. Make the data available to Patreon supporters only. Maybe throw in a few other goodies. I'd subscribe, and based on the interest in this thread, a lot of others would also. This data has real value, and right now it's not being monetized nearly as well as it could be. I'm sure 99% of that is just not having the time...you have a busy operation and there's more important things to do. That's the good thing about an intern / donut-getter. They could run this kind of thing without diverting the attention of your permanent employees. If there was enough interest, maybe this role becomes a full time gig...if there's not enough interest, the program dies and the intern goes back to getting the donuts/coffee. No real risk...seems like wins all around.

Just wanted to add that this thread has been a treasure trove of information and thank you Ron. I remember being a kid around 14 or so (8 years ago) going to Vegas with my family and I begged them to take me to your range. Finally they allowed it and I had one of the best experiences of my life, I shot just about every modern sub gun. Your staff were amazing and let me shoot just about everything .

Thank you and I hope to be in Vegas again after this COVID crap and return to your range for some more fun!!

Great idea! I’d get on board with this.

And the coffee's good, too.

Agreed!

I just reread all the pages from this thread. Great resource.

Ron, we know you are busy. Any update you can give is great. Business, rifles, your personal opinions. It’s all good.

I know it’s easy to try to find the bad things about COV19, but your time is still valued by me and others. Thank you.

I don't know how I have missed this thread?  I found it yesterday and its been like binge watching a three season show on Netfilx :)

A huge Thank You to Ron for the time commitment he has made here and the invaluable info he is passing on.

Hi Ron, any issues with Swiss or US made SiG 55X receivers cracking?
I’ve been told that they can around 15000 + round mark but If developed it does not affect function or safety but I would be interested to hear if you guys had noticed anything major other than losing a recoil spring do they seem to hold up pretty well?

Thanks

I think this is a good Idea!  Henderson Defense (or the Intern) could re-organize the data, and allow Patreon supporters to access it.  This goes just as much for the other threads HD has posted here.

HD has a unique database, and monetizing it would seem to be in their best interest, as well as the rest of us.

Agreed

I'm amazed firearms companies aren't paying them tons of money for access to the info.

Perhaps some are, and we just don't know it.  it would certainly be proper for HD to do so.  It's their business, in every sense of the word.

I see that Ron said upper receivers were wearing out before barrels do. I'm wondering if theres even a point in buying a high quality barrel like Hodge or Noveske if thats the case? I was planning on doing a build with an Aero upper reciever and a hodge barrel but maybe there's no point to having a barrel that lasts forever if the upper receiver will go bad first?

Remember, the accuracy standard at BF Vegas is hitting a 3ft by 4 ft sheet of paper at 25 yards. Keyholing doesn't matter. If that's if the accuracy standard you're willing to accept, then sure, you'll definitely wear out uppers before barrels.

Or you could be like the benchrest shooters, who go through a barrel every season or more on their competition guns. Their accuracy standard is MOA or less at 600 yards.

All depends on what you need the gun to do. @jamesk777

Thank you for the info!

@oldbrowndog

What do you think the lifespan of an upper is, independent of the barrel? I just bought back my old patrol rifle, a Colt 6920. No idea how many rounds total, but I know it's an older gun as it's the large pin lower. I'm planning to rebarrel it but am curious roughly how many rounds an upper will be good for? I've put a decent amount of rounds through my ARs, but certainly not enough to really push an upper or barrel to the breaking point on any one build.

@AZgunner

See below

In the OP here:

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

Why not just install that new barrel in a new upper?

BFV has gotten 200k rounds through some of their AR-15 receivers so I wouldn't worry about that priemum barrel not working out. Also, the USAF has been rebarreling their uppers since the Vietnam war. Before I retired from the guard in 2013 I saw numerous A1 uppers sporting 1\7 twist barrels. My arms room had Vietnam era GM Hydromatic A1 lowers overstamped to A2. AR receivers last a long long time.

That is great to hear. Thank you for the information gentleman

Here are the bolts we went through over the last twelve months. One thing you have to consider is that we were closed for three and half months because of COVID and since we did re-open, the amount of customers has only been about 40%-50% of the same time last year.

BTW..I'll update the AK thread with pics of broken SVD/Dragunov bolts and the HK thread to show were MP5-SD barrels ALWAYS fail.

V/R
Ron

Attached File

Wow!

Thanks Ron.

That's a lot of broken locking lugs and a few broken cam pin holes in there.
Be interesting to see if there's an enhanced bolt that has a longer service life over a standard bolt...

I'm curious how an enhanced bolt from an SR-15 or LMT would hold up also.  I've never herd of KAC bolts breaking but I don't know how many people have 50k rounds through one.....

i Need to come to vegas!

Damn dude. You got any that don't break?

My wife and I been out to see you guys a couple of times. She shot her first machine gun there. We will be back one day.

Anybody ID this bolt?


Attached File

I was going to comment on that....that is a Sharp's Reliabolt.
https://www.srcarms.com/shop/specials/relia-bolt-enhanced-bolt/
If you Google them you'll see there was a recall where some were breaking.
https://www.srcarms.com/update-recall-small-lot-sharps-relia-bolts/#:~:text=Some%20of%20the%20Relia%2Dbolts,have%20broken%20off%20during%20firing
I wonder if this one was one that should have been sent back or what.

https://www.ar15.com/forums/ar-15/I_broke_the_unbreakable_Sharps_Reliabolt___TWO_BROKEN_NOW__Update_Pg__5/118-658805/
https://www.ar15.com/forums/ar-15/Catastrophic_Bolt_Failure_/66-704847/
https://www.ar15.com/forums/ar-15/Sharps_Reliabolt_Fail/118-653693/

It doesn't look heavily used.

I thought maybe but wasn't sure. Thanks.

@HendersonDefense
How are Steyr AUG bolts doing?

Ron,

a few people asked about the LMT Enhanced Bolt earlier in the thread and I guess you never got around to answering them. Have you used one of these yet? I'm talking the whole BCG OR just the Enhanced bolt itself. I was gonna buy one, but only if its worth it. This is by far my favorite thread on this website, as i've referenced it countless times in my builds. You sir are awesome, and on behalf of ARFCOM, THANK YOU SIR.

I'll also pile on and ask about these.  The theory seems sound, but I'd really like to know if they REALLY offer benefits that make the cost worth it.

I'll take that scrap off of your hands. I've got...things...I make out of old bolts.

All the broken lugs I can see are next to the extractor. What happened to the carrier?

I think we've only lost 2-3 AUG bolts over the last eight years. It's hard to compare them next to AR15/M4 bolt because of the disparity in usage. The one thing that does NOT last on our AUG's are the factory translucent magazines. We've gone through hundreds of them and finally told the staff to swap out for Magpul's. The staff know I am weird about certain things and the fact that the AUG mag is very iconic for movie fans and gamers, I've always insisted on factory 30-rounders or the 42-rounders. After years of tossing them, I finally broke down and told the staff to switch over to Magpul units.

V/R
Ron

I can tell you that we've tried every bolt option out there. I can't say how much longer a certain brand did or didn't last but this is how they all ended up. As for the Sharp's bolt in the pile, I couldn't tell you if that was one that had a recall or not. We've tried everything out there and by the shear volume of use, this is what I am left with when it comes to AR bolts, regardless of manufacture.

V/R
Ron

@HendersonDefense

Ron, maybe I missed it, but you didn't really draw a conclusion other than eventually they all break. SO, if you had to go out and spend $2,000 on bolts to keep you in operation for two years and you couldn't buy any replacements until the start of year three, would you grab any new bolt you could get your hand on, colt bolts, a stack of PSA premium bolts, a stack of sharps bolts, the LMT enhanced bolts or whatever...

Thanks

@HendersonDefense
For those of us with original Steyr AUG mags...where are they failing typically?  Cracking feedlips, worn out springs, busted followers?  Be nice to have an idea of what to look out for...
Thanks!

Mine would fail to hold their shape around the "mouth" or feed lips.  This was first evident if you accidentally dropped a full mag (even if brand new), the mouth of the mag would deform enough that the entire 42 rounds would spew out all over the ground.  Eventually, it would start to not keep a fully loaded mag.  Eventually it wouldn't hold more than a few rounds.  I've always said that if Steyr fixed their magazines that the bullpup would become much more popular.

Could always get an AUG with the NATO stock so it takes AR mags.


Any Sig Virtus guns on the line?

They ALL crack at the rear of the feed lips which causes rounds to pop out when slamming the magazine into the weapon. You usually can't see it until the round pops right out of the chamber after being inserted.

V/R
Ron

I also would like to see some pic’s of a broken lmt enhanced bolt. I don’t see any in that tube of broken bolts.

What about using the LMT enhanced carrier or the Surefire OBC?  Both carriers use a modified cam pin path to keep the bolt closed longer to prevent breakage of the bolt.   Should also prevent cam pin breakage.  I don't know what the cam pin geometry is like comparing the LMT to the Surefire....but the Surefire was designed by Jim Sullivan himself.

Also, what 223/556 ammo are you using these days?  I recall you posting about liking to use Wolf Gold but I believe that has dried up these days.

I run the LMT enhanced bolts for 7.62x39 and haven't broken one either.  Many thousands of rounds in 7.5" full auto's.  I have broken an extractor though.