Dude,i know you want to hear differently but your question has allready been answered & answered with factual info,under no circumstances at any time in any way,shape form or fashion can you simply screw a Metal Halide or High Pressure Sodium buld into a standard light socket & expect it to work,it cant be done even if your an electrical engineer.To use these light bulbs you need a ballast.
Like i said if you want to get off as cheap as possible research florescent lighting for growing,all the info you need is in the grow faq on this site,while your researching FL lighting start adding up the cost of all the extra bulbs you'll need to accomplish a productive yeild,after adding up the total cost of the multiple fl bulbs & splitters needed to run them all you'll understand why i said to save up & get a real HID system instead.
FL lights work for growing but they are throw away equipment,after a few grows they need to be replaced & all the money you've spent is out the window,another reason i reccomend waiting till you can get proper lighting.