Question about hand stops, which are OK and not considered VFGs.

If it's a hand stop, it is not illegal to put on a featureless rifle.

Are you planning to push the legal limits and become a test case?

I saw one listed as a hand stop but it had finger grooves.  To use that would be looking for trouble.

I'd look up the definition to see how clear or wobbly it is.  The definition of flash suppressor, for example, seems to me to lack technical objective clarity.  I have personal opinions of it's enforceability but I'm not about to be a test case.

"(t) “Forward pistol grip” means a grip that allows for a pistol style grasp forward of the trigger."  Seems fairly clear.  If wrapping one's hand around the handguard, I'd think OK, if grasping it below the hand guard, maybe not.

Not sure how this compares or works with the vertical fore grip cited in other laws.