Okay, I admit that thread title is a little flashy. I don't believe Sharps Rifle Co. has ever claimed that the reliabolt was "unbreakable" but it is advertised as being an upgrade to stock AR15 parts and an item to make your firearm more reliable. Here's the deal. I'll start with specs, then address my initial problem with the reliabolt and then it's catastrophic failure today.

THERE IS A TL;DR AT THE BOTTOM

but first... PICS!

Broken bolt:






Gun it broke in:



Okay so here's the specs of this entire incident.

Bolt Vendor: Brownells
Time of purchase: Unknown on exact time, but shortly after the reliabolt launch and once it became publicly available.
Bolt MFG: Sharps Rifle Co.
Bolt Condition when purchased: New In Box

Firearms used with bolt (2 total)

First ever firearm used with bolt:

Home made SOPMOD Block 1.5 clone built on Spikes lower, BCM upper, Colt SOCOM barrel 14.5" with carbine gas system. Bolt carrier was a Spikes tactical. Approx 800 rounds fired. Half of these rounds were fired suppressed using a Surefire SOCOM suppressor. All of these rounds were expended in one sitting (carbine class). At the end of the class, the rifle barely went into battery due to carbon buildup but still functioned fine. The action became very slow and the forward assist was used often.

Second firearm was a MK18.

Factory built Daniel Defense MK18 SBR. Daniel Defense bolt carrier. About 2500 rounds were fired through this gun with the reliabolt, 90% of which were suppressed with a Surefire SOCOM-RC suppressor and sometimes (100 rounds or less) with SOCOM-Mini suppressor. The catastrophic failure occurred with the mini suppressor attached. All working parts on this SBR were factory mil spec Daniel Defense parts including the barrel, gas block, etc. with the exception of a BCM H3 buffer.

INITIAL ISSUE WITH THE RELIABOLT:

After the bolt was taken out of gun #1 (the Block 1.5 build) and put into the MK18 it didn't take long for the reliabolt to cause failures to eject. Lots of stovepipes. Initially assuming it was due to the SBR's unique barrel length and gas system I played with different buffers to no avail. Finally (after consulting this forum I believe) I checked the bolt's parts. The extractor had good tension but was missing either an O-ring or extractor insert of which I added (can't remember which one it was missing). BCM parts were used. Upon inspecting the ejector and spring, I noticed that the ejector spring had been clipped to about 2/3 it's appropriate size. I have no idea why this was done. I can only assume that someone at Sharps was becoming frustrated with trying to pin the ejector under great spring tension and decided to clip the spring to ease installation. I replaced the ejector spring with a replacement (BCM) and this solved all ejection issues. At this point, I was very happy.

CATASTROPHIC FAILURE:

Today I was training with some associates and performing some shooting drills that involved running from cover to cover, engaging targets and providing covering fire... reloading and moving as needed. Upon exhausting a magazine and inserting a new one, I fired two shots and then a very soft click. I rolled the gun to inspect the chamber and noticed the bolt had not closed completely. I used the forward assist to no avail, ejected the mag, racked the gun forcefully, reinserted, charged, and again... the bolt had not seated fully. I did this whole process once more. I switched to pistol, discarded the rifle, and finished the drill.

After returning to the rifle, I noticed what looked like a pebble in the barrel extension/locking lug area. Thinking a pebble had somehow got inside my magazine and then into the chamber, I extracted the "pebble" and then took out my bolt carrier to look for further damage. At that point i realized that it was not a pebble, but a locking lug. I found that I had sheared a lug off of the reliabolt.

I had a moment of surprise and triumph as I bragged to everyone around me that I had broken the unbreakable bolt.

CONCLUSION:

My factory Daniel Defense bolt has a much higher round count than my reliabolt. I also have other AR rifles with high round counts (just shy of 10k) with zero issues. The reliabolt is actually the very first AR15 bolt I've ever experienced a total failure with. I am not discounting the reliabolt completely. I think that milspec parts are the way to go when running an SBR suppressed. There is a lot of gas and pressure in SBR's compared to carbines or rifles. I have no doubts that the reliabolt would probably be okay in a rifle and maybe an unsuppressed carbine but definitely not a suppressed SBR. I don't know enough about metallurgy to comment on the S7 steel. I will stick to C158 in all my rifles from now on.
There is also the possibility that I simply got a bad bolt. I'm unaware of any recalls from Sharps. I will contact them and link them to this report as well as ask about the cut spring issue. It's possible they may have had a "bad apple" employee who was cutting corners during assembly. Bad assembly doesn't always mean bad design. But the fact that the bolt wasn't working properly from the factory AND that is sheared a lug... is concerning.

DISCLAIMER:

I'm in no way bashing Sharps. I love to see innovation and anything that is a solid performance upgrade to my rifles is a plus to me. I shoot A LOT more than most people. I hope this will help Sharps improve either their design or their QC.

TL;DR :

Bought a Sharps Reliabolt. Ejector spring was clipped from the factory and gun didn't eject. Within about 3000-4000 rounds the bolt sheared a lug rendering it useless. The reliabolt is a new product made of S7 tool steel and is supposed to be an improvement over almost all over bolts on the market.


I'll be doing a YouTube video on all of this including examining the broken bolt in detail and I'll post it to this thread when it's done. I'm hoping I can film it and upload it tomorrow but give me a few days to get it all done.

I always said if someone's going to break on of those bolts, it was going to be Dysfunction.

That's exactly what my buddy said at the range as soon as we discovered the breakage.

Great post. Sucks that S7 is going to get a black eye over this but maybe something positive will come out of R&D which will in turn make a better gen II Reliabolt. I'm all for nudging 60's tech along.
 

Move on.  Stop buying the flavor of the day parts and use proven parts with demonstrated reliabilty.

So we need to go back to triangle hand guards? Three steps froward and two steps back, but somehow the platform has been pushed forward from a tech perspective. You gotta have failures in order to learn the recipe for success.

 

Me too! I think C158 is awesome stuff but it's no secret that even C158 is prone to breakage after awhile (it typically takes quite a long time in an AR carbine. Sometimes in excess of 10k rounds or even more). And, I may have simply got a bad bolt. I inspected my bolt carefully when I got it and I didn't notice any cracks at all. If any gun would break a bolt...it would be an overgassed DD MK18 running suppressed.

I'll see what Sharps says this week. I don't think I'll go back to using it even if I get a replacement though.

Bad heat treat.  There will be more, as heat treating is done in batches.  Slick stick dude, I dig it.

I'd like to see you try to break an LMT enhanced bolt!

I've always said if anyone is going to challenge someone else to break a LMT Enhanced Bolt, it was going to be Blain.

I am not aware of any LMT enhanced bolts breaking but they can be broken.
Every company that offers bolts will have at least one break.
I believe the LMT bolts use an AerMet steel instead of S7, both should be tougher than C158 or 9310. They all require proper heat treat for toughness.

And OP, I hate to hear of your bolt failure. Often a gun will still run with one broken lug (if piece is not jammed into extension). Sharps should make replacement, but also they should investigate any failure.
I have not broken a reliabolt yet, still mostly use Colt, Noveske, or BCM for my goto rifles. Will watch these reliabolts closer now, mine had a full extractor spring minus the insert. Extraction is fine on mine (so far).

Has that MK18'had a bolt get to that point before?  Could it relate to head-space between the two guns (if that ome had a ton of rounds through it with a larger bolt head or something).  
Can't wait to see what reliabolt says.  
*I seem to remember the Filthy 14 broke a bolt or something at 6k rounds.  But I'd expect the S7 to make it to increase the life of the bolt even in an overgassed gun.

I'm interested to know how well lubed the parts were at the time of failure and what type of lube was used.

I'm going to go out on a limb here and guess that the rifle was very dry when this happened.

S7 tool steel must be up to the task for use as a bolt material, for it's used for bolts in the Barrett Model 99 .50 BMG bolt action rifle.

It's used in the full line up of  their .50 bolts.

I knew he had it in him, too...

The factory bolt has about 6.5k rounds on it so far. I gauged my throat wear about a week ago and when I received the rifle it gauged .5 on a 0 to 10 scale. It currently gauges a 3.5

I sold the original gun the bolt was in so I can't do any further testing on it.

5.56x45mm operates at a higher chamber pressure than 50BMG. That might not matter, but just throwing it out there. There's also a million and one different varibles when comparing the reliabolt for 223 AR's and a 50BMG rifle. Number of lugs, size of the bolt, recoil system/gas system, barrel length, etc.

Slip 2000, relubed within 200-300 rounds of the failure.

Lucky for you, the bolt carries a lifetime warranty

a little oil would of gone a long way

I typically shoot about 500-900 rounds in a shooting session but I absolutely clean and lube between each session. I don't think it was a lube problem. Plus... the bladed locking lugs and NP3 finish was supposed to enhance the bolt.

I'll lay it all out in the video. I suspect this is either a design flaw or poor heat treatment. I won't be arrogant and completely deny operator error but I think it's highly unlikely.

OP stated two posts before yours that he lubed with Slip 2000 200-300 round prior to the failure...

I can assure you sir, she can sink

Well OP one of the things that has always interested me about the reliabolt is their website states a life time guarantee.



Interested to see how this plays out. Please keep us posted after you talk to them.

TM 43-0001-27 lists the chamber pressure for M2 Ball at 55,000 psi, the chamber pressure for M855 at 55,000 psi., and the chamber pressure for M193 at 52,000 psi. So, how is "5.56x45mm" operating at a higher pressure? Also, my post was not comparing two specific bolts in particular, it was to show that S7 tool steel must be suitable as a bolt steel in general; referencing Barrett's use as an example of another weapon system using S7 tool steel for bolts.

Im pretty sure they got the bolt material and hardness dead nuts on 50 years ago.



As we have seen from the last 10 years, most of the junk marketed is useless and not for serious use.



They only improvements that have been worthwhile have been KAC improvements. They fix the root cause problems and dont add bandaids.



 

KAC has the best non mil-spec solution but LMT got their enhanced bolt right as well...  Other than that, every other non mil-spec bolt out there is crap including this, as soon as I saw this bolt I thought it was hype and I'm not surprised with this.

I disagree.  ARP's superbolt has been working great for the 6.8 guys and LWRC's ACB has been purchased (at least in small quantities) by SOCOM elements.



 

LMT and LWRC got it right with their enhanced bolts

I was going to mention ARP. The 6.8 case head width decreases the thickness of the bolt rim pretty significantly yet still has 55k chamber pressures. People push this round pretty hard, and the most common and cheapest factory round has been having swipes and slightly cratered primers which leads me to believe it has higher pressures.

I am yet to see a failure of the ARP superbolt. I also would bet that there arn't many 6.8 rifles high round counts though.

We must keep this in perspective- it is only one bolt that failed.

Until there is a trend, it just proves one bolt failed. I have hundreds lots of pics of Colt, BCM, etc bolts that failed in this same manner.
I also own a couple ARP 9310 superbolts, that have not failed (yet). ALL bolts are going to break eventually- if used enough.

The M16 has improved with time, and every change proves failures can happen.

Now, if these show a failure trend, I'll not use reliabolts- till then, I will.

Change is not always bad. Progress does not happen if we stand on the past -without attempting change.

I agree that most 6.8's aren't seeing as high of a round count.  I know mine don't see nearly as many rounds as my 5.56 guns.



 

hence my earlier quote

Thanks for sharing OP.

Calling it in now.

Just a question not trying to start an arguement but do you guys check headspace when you replace bolts? I had a 7.62x39 bolt come apart awhile back and I have a new bolt but have been lazy about ordering headspace go no-go gauges for it.

Outstanding.

I called Sharps just now and spoke with a lady and explained I needed warranty work done. Either this does't happen often or this is the first reliabolt that has broken as she was completely unprepared for my request. Once she got her bearings I explained my issue and that I purchased the bolt through another vendor. She instructed me to send the bolt back and that she would immediately send a new bolt out to me today. I found this interesting (in a good way) that they are sending out a brand new bolt with good faith without first receiving the broken bolt. It's excellent customer service, although it could be abused if exploited.

So I have a new bolt inbound and my old bolt will be sent back to them ASAP. So far so good. I have decided I will continue using the replacement bolt in the exact same manner I've been using the original bolt. I'll keep the factory DD bolt on hand just in case.

I'm hoping that this was just a fluke. It sounds like this was the first time she's ever had to take a bolt back for warranty and I'm sure they've sold thousands of bolts.

Great news can't wait for further reports.

that is outstanding customer and makes me want to buy from them......

To go forward you gotta go back.

Yeah, I sent them this thread and told them I--like the OP--got my bolt in the first batch.
I said that if it turns out there was a bad heat treat done, that I'd want to replace mine as well.
Oddly, they said send it in and we'll replace it with one we know has the proper heat treat--I'm wondering if they confused me with the OP (though I clearly stated "him" and "if mine" is in the same batch, etc.).

I think if there were any others we would have heard about it--I only have 2K on mine, in a very soft shooting middy, so I expect it would have lasted a long, long time.

Outstanding.

 

would firing so many rounds in one gun and then switching it to another have anything to do with this? i had always heard this was a no-no...

S7 isn't the do all wonder material guys make it out to be, AISI 9310 is probably a better fit for a M16 bolt, it's intended use as a high performance critical gear material is a lot closer than S7's forming die use.

no as long as you checked the headspace (which is why it's a no no)

but did he?? would headspace issues cause the malfunctions he experienced when he first swapped the bolt?

You got it!  

doubt he did but should have clarified that you do this when swapping and most don't which is why it's almost an automatic 'no no'

What's weird is Sharpes said they shipped ME a new, replacement reliabolt (with tracking), BUT I don't know HOW they have my address.
ETA:  they explained they confused me with dysfunction, but they're still mailing me a replacement tomorrow--since I sent them mine today (doh!).
I bought it from MidSouth Shooters for $162.74 shipped on 2/5/14...so I'm a bit baffled at how Sharpes sent it to me.  We'll see.
--
I had only emailed them saying IF IT TURNS OUT that there was bad heat treatment, that I'd be interested in a replacement--I never said, "Please send me a replacement" or anything.  They really went way beyond my expectations (and somehow figured out where I live).
--
ETA:  the reason I got it was because my sister/bro-in-law are engineers with tons of knowledge of metallurgy (he's Army--she's Army Corp--and both are very familiar with ARs), and both seemed to think S7 would definitely be a superior metal assuming it was made right (compared to the mil-spec material--158 and the other one).  I say check the headspace before you send it back; also throw a BCM and see how long it takes you to break that.  ;o)

Headspace is fine with reliabolt and factory DD bolt. I didn't test it before the malfunction but I did today.