Loose barrel extension

[el_chupo_]

Hey all, lets start this off right! I think I screwed up...

For reference, tools used:

bench vise
Geissele Reaction Rod
Hammerhead tool
1/2" breaker on HH tool
heat gun (before I thought "hey dummy, that was when you got the AAC Rocksett, dont use heat!")


I have a complete factory .300blk upper that I was trying to remove the flash hider from. This is a suppressor mount FH that I mounted probably 2 years ago, and I thought that I had used Rocksett (I had a couple little AAC blister packs), but if I am honest I wasnt really 100% sure - its been a while...

Anyways, I put the Reaction Rod in the vise, dropped the upper on, took my wrench to it with a breaker bar, as Rocksett is supposed to be heat resistant, but not high torque.

It took a wee bit of effort, and it started loosening (I thought). This is where I screwed up. This was my first removal of a Rocksett'd FH, and looking back I believe I was putting more effort than I should have (I came back and read that it should have only been 30-50 lbs to break rocksett...)

Ass soon as it loosened I removed the wrench, figuring I could spin it off with my hands, and it was then I realized the barrel had spun - the gas block was no longer at the 12 oclock position.

Pulled the rail, and sure enough, barrel spinning, gas tube bent, reaction rod/barrel extension/barrel nut for the rail all stationary...

At this point, I am almost 100% sure the barrel is ruined, but I just wanted to confirm it before I just threw the barrel directly in the vice to get the can mount off before I tossed it and got a new one.

Will suck to lose the barrel, but sometimes thats the way the cookie crumbles.

Thanks

[Jwknutson17]

You might be ok if it times back perfectly with proper torque. Next time soak that MD in water for 24 hours.

[el_chupo_]

what is proper torque spec, and how does one go about properly torquing a bbl to the extension?

[Jwknutson17]

what is proper torque spec, and how does one go about properly torquing a bbl to the extension?

IIRC it's 150ft lbs. Even with the rocksett, the barrel should have never come out of the extension. Most likely it was not torqued properly from the start, unless you really went to town on that thing. Maybe Gunz can chime in on proper way to try to torque the barrel back on. But the most likely case is that barrel is now a paper weight. Probably cheaper and less headache to just get a new one.

[el_chupo_]

I just pulled the same FH off a BCM upper, same setup/tools, and while it took a bit of effort (less than the one that twisted...), it came off as expected. Im not saying I didnt ham-fist it like an idiot, but...

Im leaning towards something simple like one of the SOLGW duty grade 9" barrels at $125 or so, and consider it an expensive lesson in buying a little better quality up front (though this bbl is from a known entity)

Thanks!

[Iraqgunz]

A. When you say factory upper (who's factory upper)?

B. You cannot torque the barrel extension on yourself. The gas port must be in line with the barrel indexing pin.

C. To correctly remove Rocksett, it is generally advised to put the muzzle end in hot water for 15-20 mins to loosen it.

D. If the barrel extension came loose, I would contact the factory because it should not happen. Barrel extension torque can vary from manufacturer to manufacturer but it's generally anywhere from 120-180 ft./lbs.

[el_chupo_]

Have not contacted them, didnt want to call them out.

Will do so next week, but not really expecting much. It was a "black friday" special a couple years back, from a large dealer/distributor local to me who was using a third party for parts and assembly - their rail, gas block, and barrel. I have confirmed with employees of the dealer I know outside of the shop (through "regular" life) that the barrel came from the same place that assembled them, but for whatever reason they did not want their name on the barrel, so it may have been something that didnt pass their normal QC, or been a cheaper set of blanks that they just finished out...

Anywho, got the FH off, and went ahead and removed the barrel as well to take a look:



On a side note - IG, can you link or suggest a good barrel vise block/adapter, for all around use? occasional AR stuff like this, but also for bolt guns and 10/22 barrels when working on things?

[556Cliff]

Looks like another Melonite job done wrong.

[GH41]

Looks like another Melonite job done wrong.

And using the wrong tool for the job. I am not making excuses for the barrel maker but a person that doesn't wrench for a living has no idea how much torque he is applying to remove something. I can pull 150 with a 24" wrench and I am not the Hulk!

[el_chupo_]

And using the wrong tool for the job. I am not making excuses for the barrel maker but a person that doesn't wrench for a living has no idea how much torque he is applying to remove something. I can pull 150 with a 24" wrench and I am not the Hulk!

Absolutely. And I do not wrench for a living, but I am far from a novice with torquing to spec with all sorts of materials and fasteners, to include the relatively delicate carbon fiber - with that said, I doubt that I was cranking on it with more than ~100 lbs, but that is an estimation with nothing to back it up.

Might I ask, what would be better tools for the job? I am not afraid of expanding the tool chest, and certainly dont want to break things moving forward either. And thanks for any suggestions, tips, and criticism. I appreciate anyone taking the time to help, even if the end result is I was an idiot.