I have a Centurion 99 and am just plain sick of the muzzle brake. I'm also considering a project that requires a barrel extension. So what I'd like to do is remove the brake and restore the original threaded muzzle. In order to stay legal, I'd either switch to a thumbhole stock or permanently attach a new muzzle attachment. But the question is whether it's possible. Is it attached in a manner that would make it impossible to get off? Is there a special method for this?