The photo show what i do to the Accura breech plug. The flame channel is drilled all the way through to be 5/32". Then a 5/16" cavity is drilled into the powder end about 3/8" deep using a 82 degree 5/16" center drill. Then the plug is tapped on the powder end about 7 threads with a 10-32 tap. At this point there is no flash hole. The flash hole is provided by drilling a 0.028" hole in a 3/8" long 10-32 Holo-Krome cap screw. Then the head of screw is turned down to 5/16", and put into place. Now the plug can be put into service, and will provide 100% reliable ignition of BH209.