I just fired my first gun yesterday, SKS, AK, and some 12-gauge shotgun. I had a lot of fun and I was wondering what kind of AR15 should I buy or should I just put one together myself (If so what parts). I'm looking for a nice price for a good gun, and decently cheap ammunition (Do not want to spend over 500 bucks). If this is too cheap, tell me. Any information would be greatly appreciated.