Some people don't know any better - Troy SOCC Low Profile BattleRail M-LOK PDW 7.6 Inch

I've owned every single handguard made by troy. This 7.6 SOCC handguard is one of my favorites. It is tight to the recieve when installed properly. If your barrel requires many shims it will leave a gap with the upper like ANY hand guard! Centering is easy as the standard usgi barrel nut will free spin ones inserted all the way before tightenin. This allows easy alignment to top rail on the upper reciever. It needs to be mentioned the indexing stud may impede alignment with upper reciever if you're using a non standard shaped billet reciever.