I could tap it, but the recess where the bolt head goes in is the size of the smaller bolt head. Trying to avoid a duct tape fix. Very nice handguard on my 6.8 pistol.I have one of those, I'll look tonight to see if mines like that. The factory threads could have been stripped and someone repaired it already. Maybe by their design. I don't have facts on the handguard, but a stripped helicoil is not fun. Will it take a larger screw?