i have decided to install a freefloat handguard. Purchased the tacticool barrel nut and all else needed. My question is how to eliminate the gap between the receiver and handguard. i have read to eliminate the tabs but the tacticool barrel nut wont thread that far. it wont thread far enough to even hit the tabs. Am i doing something wrong? also the adapter that comes with the rail will only thread to the end of the barrel nut. any help would be greatly appreciated