I have a factory installed FF rail made by YHM on my RRA tactical entry carbine. I tried to remove it using Mickey Mouse methods that failed so I ordered a YHM FF tube wrench. On a side note, this tool is worth the price, solid. While waiting for the wrench to arrive I soaked the locking ring on the FF tube in Kroil for about a week.

I tried removing it today and failed miserably as well as the locking ring. Since it was factory installed, I thought they used a bit of lock-tite (who the hell at RRA thought this was a good idea?) so heated up the oven and stuck my upper in for a few minutes to heat it up. Then mounted the upper into action block (is that the name?) and into a vise and went to work. The tool ended up breaking the edge out of one of the teeth that is used to tighten and loosen the locking ring. So I thought bad luck and tried again on another tooth. This time I thought I'd give it a solid and quick push to unsnap the seal on the threads and sheared another tooth edge off the locking ring. There are only 4 teeth (the recesses in the collar where the tool fits into) and I just broke half of them. I stopped and left a message for both YHM and RRA to call me in the morning when they get in.

Anyone run into this kind of thing or have suggestions on how to get this thing off? I want RRA to supply me with a new locking ring/collar since they F'ed up and used (at least I'm pretty sure they used) lock-tite when they shouldn't have.

Which direction are you going with that jam nut?  This might sound counter-intuitive but you actually want to be screwing that jam nut clockwise (once the ff tube is screwed on to the barrel nut, the jam nut is "un-screwed" to lock the ff tube into place).  

At this point, you'll probably need two sets of hands and you'll want that upper in an upper action block.  Have one set of gloved hands holding onto the ff tube and un-screwing it (counter-clock) while the other pushes clockwise on the jam nut using the YHM tool.

Since clockwise or counter-clockwise is subjective relative to which end you're looking at let's use this. I am screwing it towards the upper receiver or as you said, clockwise when viewed from the muzzle. You may be right about needing the second set of hands and unscrewing the tube at the same time. I'm a little nervous to try seeing as I've only got 2 more useable 'teeth'.

OK, sounds like you're going in the right direction w/ the jam nut (clock-wise toward the receiver).  However, when the jam nut is doing its job, it is more inclined to actually have that FF tube travel with it vs. breaking free from it (resulting only in tightening the whole works towards the receiver).  Having that jam nut and the ff tube being torqued in opposite directions simultaneously is the key.

I think if you can find a buddy to help you out you'll get this thing off - the one with the stronger hands should take the free-float (must wear gloves, too).   If you end up needing more torque than a pair of gloved hands, you can cut a strip of bath towel the width of the tube, tie it in a loop, wrap the loop around the ff tube a few times, and use a breaker bar with plenty of towel to cushion between the breaker bar and the tube.  This would risk damage to your tube and too much torque could damage your receiver so I'd use this as a last resort.

I have removed that tube from that rifle recently  - there was no thread locking compound on this particular unit.  I believe YHM only recommends use of a thread locking compound on the end-cap.

Thanks triggerfin, I think I'll go give it another try again with your method. Sounds like a solid solution.

Well I had every confidence that it would work but it didn't. I felt that we were putting a tremendous amount of force into it and had to stop before something else broke. Either another tooth or we twisted the upper. I really thought that we were going to break the upper we hit it so hard. I don't know who put this thing together but they must have had arms and wrists of a gorilla. At this point I think maybe the manufacturers, either RRA or YHM, should be the ones to do it. Thanks for the advice.

Damn, sorry.  You could freeze the thing overnight and give it another whack in the morning...

If you are able to rescue that tube, shoot me an email w/ your address and I'll mail you a replacement jam nut.

Thanks for the very generous offer. I don't want to have to take yours though and leave you lacking. I think the companies will be able to replace them without too much fuss and that won't leave you with a tube and no lock. I tried freezing it earlier today with no success. Maybe I'll try again tomorrow with this above method. Thanks again.

Well I tried the freezing thing and that didn't work either. I'll call them both again tomorrow and see if I can get help from them. What a pain in the ass.

Well I got an RMA number from RRA. They said that they would use a propane torch on it and melt that locktight. I went to a friends house today and we did the propane torch thing and lost another tooth trying to get it off. What a pain in the ass. Now I have to send it in.

Hmmmm....not belittling your troubles at all, but there have been several people who posted here about the YHM tubes coming loose.  Obviously, whatever the folks who put your upper together used, they've solved that problem!

Good luck...

Probably red loctite.

No probably about it. Definitely red loctite. The thing is, the instructions specifically say not to use any locking compound.

I have heard you can use blue to prevent possible loosening but never red.

Well I got my upper back from RRA today and they made good. They removed it for me and provided me with a new lock nut so all is now well. Thanks for everyone's voice on this.