An AR is going to be a pretty big handicap in a lot of ways. Wind, of course, is an issue, but a larger concern is that small, slow bullet makes spotting hits a lot harder on steel. The steel is usually so shot up that the only way the RO can call hits is sound, and if the plate move. Many times, a .223 just wont swing the plate. Not saying it can't be done, and definitely cant say it won't be fun....but it will be tough.
Do some poking around your area, chances are there is a state or regional lever club that shoots "PRS-Style" club matches that will be a lot less formal, and a good way to wet your feet and see if its something you like. If it is....you will be getting a bolt gun pretty soon.
