MH lighting question

I plan on doing a CFL grow but have a 70w MH that I got for free. It is a medium base so it can screw into a normal light bulb socket but from what I see MH and HPS bulbs need a ballast. I plan on getting some of the all weather sockets (the ones that can plug into a regular outlet) and making a reflector hood for them. I'm wondering since the MH bulb has a regular base, can I plug it into a regular socket or do I still need some sort of ballast? I'm assuming it would work, but would it be safe? I just want to use one of these MHs for vegging plus some CFLs. It is a small wardrobe grow. what do you guys think?