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1919A4 Build Tutorial 3
Drill guide is supplied courtesy of Halo Manufacturing
    Clamp the receiver together, with the backplate, top cove and trunnion
in place and drill all the rivet holes with the proper sized drills.
Disassemble the receiver and de burr all the holes and clean all the chips
from the side plate and inside the receiver.
    The next step is to chamfer the holes with a 60 degree countersink. Follow
the drill guide for location and you can use the rivets to set up the drill press
for the depth. Take your time countersinking, the rivets need to be flush, and
not below the surface of the plate, specially the ones on the bottom plate.
Use the countersink to break the edges of la the holes to remove any burrs
from drilling.
    Now it is time to rivet. Make sure to remove all chips and burrs from all
the parts before beginning. First rivet the pintle pad to the side plate. Crush
the rivets from the back in a press, only do the 2 shown, then grind them
flush