Originally Posted by SSGN_Doc
I don't get it myself. But that was the case when they made the ruling in the '90s.e
But most AR15 receivers don't have the third set of holes for the interrupter either.
Your right but what if it was drilled in there , yet you still had a semiauto fcg in it without the shelf removed . It would just be another nonfunctional hole . I think they did that because they were previously F/A converted pre 94 that werent supposed to ever get on the boat over here .