I left a message w/ DPMS to find out, we'll see if they call back.  I've tried to get it off with a wrench but I don't know if it is LH or RH threads.  I also want to know what threading they used so I can get other muzzle brakes or flash surpressors.  Any help would be appreciated.

On a side note, I was able to get the front sight off tonight so I could take off the handguard to install the included sling swivel to mount a bipod.  Why DPMS doesn't just install it at the factory is way beyond my comprehension.  But because I couldnt get the flash surpressor off I wasn't able to completely remove the handguard from the barrel, so I had to drill it while on the rifle.

FYI...called again and DPMS confirmed that the barrel is threaded 5/8"x24 w/ RH threads.