I am building shelves in my basement on concrete walls. I am using metal studs to hold my wood cross pieces for my shelving. My question is, what ways can I attach the metal studs to the concrete walls? Can I drive bolts through the studs into the wall? If so, is there an easy, effective way of doing this? I know that there is single shot tools that can be used but I don't have one and didn't want to get one for a one time use. Thanks for the advice?