Looking to get into the AR hype but I know pretty much nothing about them. I had planned on buying my wife a rifle to start hunting this year but figured hey if I could by a AR that she/we could use for deer hunting I could use it as my excuse to get one. So where do I start. I've looked at 100 different websites and don't know where to begin. What caliber would be best? I'm thinking 6.8 but need some feedback.(again don't know much about these calibers either). Is 6.8 a good caliber for a woman shooting? I'm thinking I need at least a 18" barrel if not a 20"+?? Any recommendations?