I make hammers for the Marauder. The most recent one is being made out of some sort of 1.25" axle shaft. I turned it down to diameter on the lathe with no issues, and drilled thru for the striker hole and spring counter bore with no problem. When I went to cross drill it for 8-32 and 10-32 tapped holes, the cobalt drill wouldn't touch it. What type of drill bit do i need to drill this HARD steel?