01-24-2018, 02:18 PM
I bought a PT&D lapping tool with the thought of gaining as much accuracy possible from each build. I've lapped 2 of the 4 uppers I've built, the Anderson and Spikes Tactical, both in the vertical position. The Anderson was the easiest and done by hand while the ST took the drill (VERY slowly) about 5 minutes to fully clean the surface. Both the BCM and AERO required heat to install their barrels and would have required heat to allow the PT&D tool to be used thus I felt the possible gain in accuracy was offset by the mating of each upper to it's barrel.