Re: Muzzle brake help
Have you tried asking Roscoe?
The FTE is a really good brake but as Rob said, the barrel O.D. has to be turned down a good bit behind the thread termination. This is going to give you less shoulder for your Cyclone to tighten up against. I personally try to keep the shoulder contact area as large as your barrel contour will allow for any screw on suppressor.
There are several out there that will go straight onto your threads and stop without having to time the shoulder or use washers while keeping the max barrel O.D. right up to the suppressor threads.