I did not know that.All their old cf handguards were glued on--they made the 338f in both the old "lr308" chassis and the "G ii" chassis -
I have a G2 in 308 with a non glued on CF HG and have read quite a bit about G2 related problems.
OP has a much simpler issue if he has a normal DPMS cut as HGs will be easy to find.