Hi Mark, These are my bits of choice, 2 side cutters, they make a nice clean hole.

http://www.irwin.com/tools/drill-bits/hand-brace-solid-center-auger-bits

You can get them with a hex shank for the power drill. 1-1/2" and 18" over all, 12" auger. I have been using the shorter ones in my boring machines. Had to cut the tapered square off and adapt a clean 1/2" shank.

What a joke the ship augers are. I guess they are fine of electrical work.