[MultipleParadox]

I'm going to piggyback on that thread real quick as I have somewhat related issue:

I own a King Arms M4 as well, that came with the Larue RAS (7")
I've been trying for the life of me to unscrew the flash hider and never achieve to make it even a little. I did try to soak it in hot water before hands, didn't help.
Even decided to use Vise-Grips+Towel, and all it did is what you'd think: scratch the flash hider :P

I'm starting to think it's not removable, in which case I'm not sure how I would be supposed to be able to change my upper/barrel (can't slide RAS far enough because it stucks on the gas-block which is blocked by the hider... get it?)

Any thoughts?

Thanks