this is my first post so a big hi to all.well i bought my first ar about 3 months ago without seeking any kind of council and i guess i got the shaft. so here it is i'm told it's a parts gun,oly lower with the upper receiver the same color but the barrel is a posphate kinda looking and it has a heavy 20" barrel that has a step down about an inch from the muzzle also it is nonchrome lined.The marking on the upper next to the sight is af that kinda made together,the gun seems to function fine,....... so please give me some help.....thanks pooh