thanks for the information.j870sm said:I would just give it a look over, you should be able to tell if it has had extensive use. If I was concerned about anything it would be the barrel, look down it and check out the rifling.
I do keep a set of pins and springs just in case but you can order these from many different places and can usually pick them up at gun shows. I wouldn't be to afraid of buying one used.
I can tell you this though, once you get to shooting an AR you will be hooked and probably amazed at the accuracy. They seem to digest just about anything and perform very well.