how is a muzzle brake permanatley installed on a barrel and is there a way to remove a permanatley installed muzzle brake without cutting the barrel
DEPENDING on the type of rifle you have, the brake is either threaded in, or pressed on.
I have a Stoner SR15 which had a pressed on and locktighted fake brake. It needed heating up with a torch until red hot, in order to remove, by clamping it with a BIG wrench.
If yours is the screw in type, look for a push pin, somewhere on the bottom part of your brake, which looks like it was ground smooth and blued over.
In any case, I think this is a job for your gunsmith.
I have installed a birdcage "look" brake from gunsmoke which was screw in, then pinned for permanent installation.
hope this helps.