All it took for me was a .035" flash hole.

The 5/32" flash channel that grouse recommends does in fact help keep accuracy consistent. i noticed yesterday when shooting our apex that uses the factory flash channel, after 6 shots, i took 2 more and had them in the same hole, shot another that went 1 1/2" to the left, fired 2 more and the were still over on the left and started to climb higher. Keep the flash channels clean for consistent accuracy, thats all there is to it.