Anyone know what size the faux suppressor set screw is?  This is the one that threads into the bottom of the front sight assy to hold the suppressor secure.  #96 on the parts breakdown.

Found it finally.  it's a 3mm setscrew.

Is that the length? What is the thread - M2, M3?

No idea.  I actually took the recoil tube to the local hardware store to find something that fit.  I ended up purchasing a 3mm x25 straight-slot screw and cutting it down till it was flush with the front sight assembly, then blued it.   This was so I could secure the HK Specialist 3 lug adapter for the new SBR.  I did not pay any attention to the thread pitch.

Of course now everyone and their brother now have the Swarfworks style adapter I actually was trying to find.