First rifle recommendation?

I am a long time lurker here and have finally decided that I want to exercise my 2nd amendment right. I have never owned a firearm, but I have visited my local firing range and used handguns. I am looking for a rifle and was wondering what all of you think would be a good option as a first time owner. First, lets be clear what my intentions are with this:

• I am not interested in hunting
• I am not very concerned about the defense of my home and property
• Really I want a rifle that I can take to the firing range every once and a while and get good at shooting accurately.

I want to own it for the sake of having it in case there were ever some sort of complete break down in civil order or zombie uprising that put me in a position that I was responsible for my own safety, but considering that this probably won't ever happen, just something reliable and inexpensive that I can use at the range. I don't want a .22 because I don't think it would be effective in my imaginary doomsday situation. Thanks!