For the tubes, there were commercial tubes made without the slight taper on the back of the tube. The best way to check is to actually measure the tube diameter with a dial caliper.
Commercial Tube Diameter 1.168
Mil-Spec Tube Diameter 1.148
Its the exact opposite of what everyone really has been wanting, a 17 slide on a 19 frame for the grip reduction. Good thing for 3rd parties that will do that to a 17!