Thanks Iraqgunz
As said I already tried putting the whole upper in the freezer but that didn’t work
When I cut a nut off I make the cut perpendicular to the threads. If this nut was Loctited no amount of penetrating oil is going to help. In that case splitting the nut, maybe splitting in two or three cuts may be your best bet. You want to make multiple shallow passes every time looking for threads. The first indication of threads will be very faint, you might want to use a magnifier to look. Pry the slot open with a large screwdriver. If you get into the receiver threads a little bit it is probably no disaster. To break Loctite you need a lot of heat. This might be a problem as the receiver would be a very good heat sink and carry the heat into your action wrench.
Another option you could have is to sell the TRX-E rail on the EE. Then purchase a rail that mounts to the standard barrel nut like the ones from www.apexhandguard.com or www.centurionarms.com . Also, I have had good luck using this graphite free anti-seize product when installing barrel assemblies or on other metal to metal parts that might need to be taken apart later.
Lubro Anti-seize
LM508 - Special assembly lubricant for threaded connections exposed to high temperatures and adverse operating conditions. Protects nuts and bolts from seizing, galling, rust, pitting and damage.
Prevents corrosion between dissimilar metals, resists water and salt spray. Allows for easy, damage-free disassembly even after extended service periods.
once you break off enough of the teeth switch to a pipe wrench and a cheater bar. 
Would that work? I’ve run into issues in other applications where the pipe-wrench deformed the nut into the threads and locked said nut on tighter.
You said you were using the “tool supplied by Troy with your TRX-E”? The tooth pattern on that tool is made for the barrel nut supplied with the handguard. It does not line up correctly with a standard nut. Get a standard barrel nut socket or tool and you’ll get a lot more grip on it and most likely an easier time getting it off.
Best of luck, they are a nice system and worth the fight.
Good catch. I just noticed this.
The troy barrel wrench has two sides to it. One side for the standard nut, and the other side for the troy nut.
Always has for me and is still my last resort. I spent a couple years as a plumber so their use isn’t foreign to me.
The right tool for the job usually works:D The teeth on some barrel wrenches that are rail specific are just a little off from regular wrenches. I had a hell of a time with a DD Lite a little while ago. I was using an old supplied barrel wrench(supposedly)and it just wouldnt catch good. Had to borrow another one from someone else.
Kroil has worked miracles for me on guns and other things.
And I used a pipewrench on an aluminum housing, similar to an ar reciever. I wrecked the threads and the housing.
Now there’s some handy information…Thanks!
Thanks for all the input guys. Just thought I’d get back to you with the redult. I ended making a fine cut with a hacksaw along the nut. Just when I started to see the threads kinda looking up I stopped. The cut had weakend the nut to such a degree that it came off without using much force. On inspection the threads on the upper were unharmed and the Troy nut spun on like a charm. Once afain thanks for all the advice!
That’s the old wrenches. The new one has only one side.
I took both barrel nuts out last night to try it and yes, the tool for mine (I guess a new one) ONLY fits the supplied nut. There is no provision for removing a stock barrel nut with the supplied tool from Troy. Honestly, the old tool sounds like a better option.
Good luck.
Though it must be added that the old Troy tool is inferior to the Armorer’s Tool when it comes to removing the original nut.
That big silver in the center is a professional grade Troy wrench. It works like a champ!
Will that work on the factory nut or only on the Troy nut?
Just thought I’d revive this thread instead of creating a new one; I swapped handguards on my Oberland M4 a couple of days ago, and contrary to The_Swede’s experience the barrel nut on mine came off with very little force. The threads were properly greased.
I now have a Troy VTAC Alpha Battlerail on there instead (even though that rail is designed to work with a standard barrel nut it was less work to just remove it to get the delta assembly off than to cut the delta assembly off as I know many will do).
Oh, the front sight base on Oberlands ARs are not F-marked, nor are the barrels parkerized underneath the gas block.