WTF would cause this?

[-Nick-]

Moral of the story: Don't be the monkey who didn't use anti-seize and just rocksett unless you want the brake PERMANENTLY affixed

Original Post:
I'll preface this with I'm glad I didn't sell it before I removed the brake. I'm not sure what caused this and it just cost me $400+. I went to remove the Surefire MB556SSN brake so I could replace it with another brake for resale since this brake is hard to come by, and when I tried to get it off it was damn near impossible. It finally broke loose... literally. The photos below show what's left of the Rainier UltraMatch barrel where it threads on. A piece of the crown is even missing. Bad threads? When I installed it there was zero issues and it went on smooth and timed up perfectly.

 

[bschneiderheinze]

Ouch

 

[LawnMM]

Bad steel or threads, call Ranier

 

[Gunfighter14e2]

Gas erosion, caused by the brake and barrel threads not interfacing correctly.

 

[-Nick-]

Looks like the brake threads are fucked also. So now I'm out $550+... I don't think it's gas erosion. There's only about 250 rounds on it.

 

[Trigger Monkey]

What is the barrel length?

 

[-Nick-]

What is the barrel length?

18" with Intermediate gas length...

 

[Trigger Monkey]

Send it to ADCO, have them cut and crown the barrel, rethread, it'll probably end up at 17" but you'll save the barrel and you're not out as much as you think.

 

[-Nick-]

Not to sound like a jerk but that looks like a over torque or a cross thread.

I know it wasn't cross threaded and if it was then the threads would have been jacked up all the way back. I timed it properly and the crown has at least 1/4" of room between the end of the inside of the brake and the tip to prevent that.

 

[-Nick-]

Send it to ADCO, have them cut and crown the barrel, rethread, it'll probably end up at 17" but you'll save the barrel and you're not out as much as you think.

I sent a message to some smiths to see what it would cost to do that already. The brake though I'm SOL on since there's no way to fix it. I might have it cut the barrel down to 12.5 and re-ported for an SPR.

 

[opeagle]

Looks like over torque. Now that could have been a combination of variance between barrel thread and brake thread engagement.

Sorry, just posting my impression. I'd also sent it to ADCO to have them shorten it and re thread the barrel.

 

[-Nick-]

I don't think I torqued it down that much. I just did it hand tight, but I won't rule it out since it wouldn't be the first time I've over-torqued something. I guess I just don't see how it would create such a deep groove into the metal rather than simply pull off threads and why it wouldn't do it to all the threads.

 

[Tacsnipe73]

Did you put any kind of locktite on? Red....?

 

[tipper]

Lets see the brake inside, no way that screwed on easy by hand.

 

[drifto808]

From my experience on working on cars it looks over torqued also. Did it thread on smoothly at first? Or did it give a bit of resistance?

 

[-Nick-]

I used the rock-set that comes with the SF brakes. It screwed on easy and I hand tightened it. It started to screw off easy enough but after maybe 3/4 of a turn it went stiff and didn't want to budge. I ended up using a lot of break free and then eventually muscling it off. It's a recant brake so there's no real way for me to get a good pic of the threads inside.

 

[tipper]

I used the rock-set that comes with the SF brakes, I think you have to really heat it up to break it free, Like red hot. Would never use that if there was a chance it had to come apart again.

 

[opeagle]

You drug something, backwards through the threads. Could have been a burr or threads that got eroded.

 

[tickled pink]

Next time heat it up with a butane torch if it won't come off easily. Ask me how I know. Also if you can not get a screw lose on a bolt action rifle you can heat it up with a soldering iron to break it lose. The heat also frees up locktite & rust also.

 

[shoot4fun]

I used the rock-set that comes with the SF brakes, I think you have to really heat it up to break it free, Like red hot. Would never use that if there was a chance it had to come apart again.

NO!!!!!!!!!!!!
Rock-set requires you soak the area in water for at least 24-48 hours. Heat WILL NOT loosen it. The Rock-set is, IMHO, what messed up the threads when you forced the brake off without soaking first. You must of put some kind of big boy torque on that thing getting it off!

 

[wfjames22]

Rocksett is a ceramic adhesive that will withstand 2000+ degrees but will not withstand shock. Therefore, to remove a muzzle device that was put on with Rocksett, you need to break the ceramic bond with shock...ie a few good whacks with a hammer. I have done this many times with no issues. Heat will not do shit to properly applied Rocksett unless you melt the muzzle device off of the barrel.

ETA...according to Flexbar, the manufacturer of Rocksett, water will break it down. Personally I would rather use a few light taps with a hammer to break the bonds rather than soak the end of my barrel in water for hours on end, but it will work.

 

[BGE541]

Nick hungry... Nick want muzzle brake.... NICK SMASH!!!!!! Sorry man that stinks...

 

[TexasGunTrustLawyer]

Okay . . . Do I beat the rockset with a mallet or do I soak it for 3 days in water or do I sacrifice a chicken and poor chicken blood on it as We dance around a fire in the forest under a full moon to get the rockset loose?

I lost track back there!

 

[rideHPD]

Rocksett is a ceramic adhesive that will withstand 2000+ degrees but will not withstand shock. Therefore, to remove a muzzle device that was put on with Rocksett, you need to break the ceramic bond with shock...ie a few good whacks with a hammer. I have done this many times with no issues. Heat or water will not do shit to properly applied Rocksett unless you melt the muzzle device off of the barrel.

For God's sake no, that is not what you do. As previously suggested Rocksett is to be partially dissolved by (ideally DI) water over a 24-48hr period. You can vibrate it loose, but you can screw up the finish or knock something else loose or break something, a risk that is completely unnecessary. It's not just going to spin off, but it will remove the strong chemical bonds.

Back on topic, I would agree with the hypothesis that Rocksett played a part in the demise of the muzzle, as the parabolic shape of broken area is consistent with a shear failure in torsion, but that surface texture looks exactly like the muzzle face of my AK. Does the flaky stuff chip off easily? If it were from overtorquing/Rocksett, you would really only expect very localized deformation and not have that much material break free, and the surface texture would either have striations in the direction of the rotation or fractures roughly parallel with the bore, not scattered all about. That's indicative of gas flow. If we had a higher resolution picture that was blown up we could determine more. [MENTION=17447]High Binder[/MENTION] will know more about this than I.

 

[elfster1234]

Maybe someone who's name starts with f and ends with a d came to your house while you were not home and took a blow torch to the end of your barrel in order to lower the accuracy of your rifle? Damn you ferdinand!! You got to look out for that guy!

I'll preface this with I'm glad I didn't sell it before I removed the brake. I'm not sure what caused this and it just cost me $400+. I went to remove the Surefire MB556SSN brake so I could replace it with another brake for resale since this brake is hard to come by, and when I tried to get it off it was damn near impossible. It finally broke loose... literally. The photos below show what's left of the Rainier UltraMatch barrel where it threads on. A piece of the crown is even missing. Bad threads? When I installed it there was zero issues and it went on smooth and timed up perfectly.

View attachment 32772View attachment 32773

 

[19Scout77]

I used the rock-set that comes with the SF brakes, I think you have to really heat it up to break it free, Like red hot. Would never use that if there was a chance it had to come apart again.

You may be clueless...but at least you are consistent. You make for the perfect inverse barometer when it comes to shooting info. Just take what you say, and do the exact opposite.

 

[-Nick-]

For God's sake no, that is not what you do. As previously suggested Rocksett is to be partially dissolved by (ideally DI) water over a 24-48hr period. You can vibrate it loose, but you can screw up the finish or knock something else loose or break something, a risk that is completely unnecessary. It's not just going to spin off, but it will remove the strong chemical bonds.

Back on topic, I would agree with the hypothesis that Rocksett played a part in the demise of the muzzle, as the parabolic shape of broken area is consistent with a shear failure in torsion, but that surface texture looks exactly like the muzzle face of my AK. Does the flaky stuff chip off easily? If it were from overtorquing/Rocksett, you would really only expect very localized deformation and not have that much material break free, and the surface texture would either have striations in the direction of the rotation or fractures roughly parallel with the bore, not scattered all about. That's indicative of gas flow. If we had a higher resolution picture that was blown up we could determine more. @High Binder will know more about this than I.

A piece of the crown fell off after I finally got it off. I'll see if I can get some better pics later today.

 

[wfjames22]

For God's sake no, that is not what you do. As previously suggested Rocksett is to be partially dissolved by (ideally DI) water over a 24-48hr period. You can vibrate it loose, but you can screw up the finish or knock something else loose or break something, a risk that is completely unnecessary. It's not just going to spin off, but it will remove the strong chemical bonds.

Drama queen much?

If you are hitting your muzzle device hard enough to "screw up the finish or knock something else loose or break something", you really shouldn't be working on your weapons. Personally, I use a 4oz ball pein hammer for this.

I did learn something about the water aspect though through an email to Flexbar (Rocksett's manufacturer) and will amend my post to reflect it so I am not spreading false information. I would rather use a few taps from a baby hammer as opposed to soaking the end of my barrel in water for hours on end, but apparently it will work. Transcript of email below:

Frank,

Thanks very much for using our product.

Those are really the best methods for breaking the bond. The adhesive cures to a hard ceramic so the light taps crack it. Once cracked -- relatively easy to remove.

Water will break it down as well.

Thanks again for your interest. Please let me know if you have any further questions.

Sincerely,


Louis A. Valenti
Sales Director
Flexbar Machine Corporation

 

[Mike_Honcho]

OP - can we see the muzzle device? Is the portion that is missing from the muzzle of the barrel anchored to the device, or is this what fell off?


FYI I have rock settled several things; heated up a couple when I didn't know better, and used cheater bars - everything was "A-OK". I think you have a little something else going here.

 

[Masked]

I haven't seen this yet on a gun/barrel etc...But, I HAVE seen this before on a Server Rack.

One of my current customers had their racks installed by an "amateur" who literally rockset every single 12/24 and 10/32 in the entire rack...Boy was that a dream come true.

1/2 the threads on the screws looked like your barrel...Had a few nuts that were completely stripped...I actually ruined a brand new 8amp Dewalt trying to get them out (Might have been the drill, itself because they just handed me a new one when I returned it)...After about 20 minutes with the 6amp I said fuck it and pulled out the impact wrench...Took me @ 1hr to get the other 50 screws out with the impact wrench but, it wasn't pretty.

I'd say your issue is purely one of rockset...I've heard of "red loctite" causing similar issues but, if I'd never worked on that rack, I wouldn't have believed rockset could do it, either...

 

[MLC]

How long was the cheater bar you used?
Wow, man.

 

[nuclear_shooter]

I'm not entirely convinced you could do that kind of damage by hand (even with a breaker bar)... it looks *proper* fucked...

 

[mallrat]

Reminds me of some of the fasteners I've dealt with working on semi-trucks. Usually dissimilar metals (steel into aluminum, etc.), corrosion acting like a chemical weld seizing the two components together. Started with PB blaster, heat, hammer, cuss, hammer, heat, cuss some more, lol. Of course that's stuff that's probably been assembled dry, then exposed to a million miles of roadsalt, grime, varying temps, etc. Heat usually helps with corrosion or red loctite, light application of hammer helps with corrosion and apparently rocset, I wouldn't have guessed water will break down rocset, but now that we know that soak the brake in a bucket. See if you can retap it or clean the threads. Good luck!

 

[bentbolt308]

They leave a lot more threads on the end of the barrel I tried to put on a break that I have had on other barrels and it bottomed out on the threads and still had over .150 of travel still to fit against the barrell.

 

[-Nick-]

I used a regular wrench and no real "breaker" bar per say but I did put some muscle into it after I tried using break-free to get it off. I'll see if I can get some better photos up. If the supplied rocksett is the issue then I'm a little disappointed with SF since you really have to take these brakes off every 800 rounds or so since there is usually 1/4 of exposed threads on the brake that will foul up and develop a false crown over time which needs cleaned off. I guess lesson learned the hard way.

 

[CMH]

Classic stainless thread galling. Very common when using stainless bolts and nuts together with no anti-seize, which is essentially what you have with a stainless threaded barrel and a stainless brake. Was probably exacerbated by the rockset. Stainless to stainless always gets some sort of anti-seize if you ever want it to come back apart. Or you can't use stainless on stainless.

 

[pmclaine]

HMMMM...Looks like by using Rocksett and a cheater bar you might be able to make 1/9 into a 1/7.

 

[rideHPD]

No drama, just when I read about someone hitting something with a hammer on this website now I assume the worst, which is why you have to be specific. People on here will not think beyond what you say half the time (or use the dawn search function), and it drives me crazy, do for that I am sorry if I aggravated you.

And to the OP please do post all of those images and show where the chunk of the crown came off, it'll help. Try to get good contrast/low flash.

 

[mtrmn]

I didn't have time to read all the way through this. If it's a stainless bbl, then stainless will pull this kinda shit even without a threadlocker. Stainless is pretty soft and tends to "smear". Threads will lock up for no reason whatsoever and will wind up looking like your bbl. I put my adapters on with a bit of nickel antiseize (high heat) and torque them to 30 ft pounds. Just my experience.

 

[buggsb]

The good thing is that ADCO can cut, re-crown and rethread the barrel for around 65 bucks. If the barrel diameter is big enough you could get it threaded at 5/8-24 and have your brake rethreaded to match. Not as big a cost as you might imagine. Or just get the barrel cut and rethreaded and get a new brake.

 

[-R-]

Classic stainless thread galling. Very common when using stainless bolts and nuts together with no anti-seize, which is essentially what you have with a stainless threaded barrel and a stainless brake. Was probably exacerbated by the rockset. Stainless to stainless always gets some sort of anti-seize if you ever want it to come back apart. Or you can't use stainless on stainless.

Nailed it... Stainless to stainless always gets anti-sieze. Not sure if that is the case in the firearm industry as well, but thats the general rule of thumb when working with stainless.

 

[-Nick-]

HMMMM...Looks like by using Rocksett and a cheater bar you might be able to make 1/9 into a 1/7.

LMGDAO.... That's fucking awesome man...

 

[Tacsnipe73]

If you want to save your $140 brake, I would recommend soaking it water over night and then using a 55 mm extractor to remove the remaining piece of your barrel from the brake. Money doesn't grow on trees, and neither do surefire brakes.... just my 0.2

 

[LRRPF52]

The good thing is that ADCO can cut, re-crown and rethread the barrel for around 65 bucks. If the barrel diameter is big enough you could get it threaded at 5/8-24 and have your brake rethreaded to match. Not as big a cost as you might imagine. Or just get the barrel cut and rethreaded and get a new brake.

This is what I would do as well. Neither part is lost. A good barrel smith/machinist can fix both.

There is a lot of bad info in this thread. Things you should not do:

* Apply open flame or torches to rifle parts. Why? Flash heat treat into brittle condition, metallurgy compromised.

This is the point at which we put ego aside, and think about what's going on with the physics of what those who suggest "just heat it up with a torch until it glows red hot" are suggesting.

Wish there was a way to filter out bad info here a little better. For those that have backyard gunsmith suggestions, you might consider taking a machining course, study some materials science, metallurgy, and think about what temp stainless steel has to be to reach red hot on the chromatic spectrum. There's a reason we don't use stainless on machine gun barrels.

 

[cal50]

You should be able to run a tap in the brake to chase the threads clean.
The barrel threads need faced off and set back, a simple lather job.

From lack of corrosion in the pics the threads were likely damaged when the brake was put on or taken off. If it came off hard that is likely the time the damage was done.

 

[tipper]

He was not in the dark, he put this on & used the rock set. Then cleaned the threads to make it look all shinny. An stupid fallows .

 

[-Nick-]

He was not in the dark, he put this on & used the rock set. Then cleaned the threads to make it look all shinny. An stupid fallows .

I didn't clean anything. What you see is what was remaining after I took it off.

 

[-Nick-]

I'm going to send the brake off with the barrel when I have it cut and re-crowned so the smith can run a tap into the brake. I appreciate the useful advice and I'll know better next time.

 

[mallrat]

Looks exactly like some of the lugstuds I've dealt with. The nut starts coming off okay, then something starts digging into the threads, and the material building up between the threads digs deeper and deeper until you either break the stud, reach the end of the threads, or run out of torque. And yeah, the damaged stud looks shiny because of the smearing action of the material passing over it.

Soak that brake in water, if you're not already, maybe you can save it. Okay, you posted while I was typing, that'll work, too. Be sure to inform them that you used Rocset and it can be dissolved with water. They should already know that, but I don't like to assume. You might save some time/expense.

 

[Bill Larson]

"Thread Galling"....................Any decent machinist can fix that.Looks to me like you would`nt have to shorten barrel..... just touch the crown...remove galled section.... rechase threads..... 1 man hr.machine time.
Use a bit of anti-sieze in the future.