Most FN Metric barrel muzzle threads are left hand and metric. The exact size I don't have in front of me but easily found out. The problem is the die is usually alot of money because it is not common in the US. However there is a flash hider made by DS Arms that has a right hand thread and is a common size so you can get the die at ACE or Home depot! Just a thought, of course you will have to trim the old thread off and take it to the maj. dia. of the new right hand thread. Not that hard really.