Originally Posted by ole-cowboy

I have read on forums two different ways to deal with this,

1) is to shave material from the bearing surface of the barrel nut, to allow the nut to sear deeper. This would have to be done very slowly and evenly

2) you already mention is to grind down the offending tooth, this would have not have anything to do with the fore-end from lining up, just allow a space for the gas tube.

I got mine to line up using a german torque wrench and set it to "gutentight"