I had some feeding issues when I first got the rifle and noticed there was a feed ramp problem. So I decided to grind and polish a new ramp. I took her to the range and she shot flawlessly. Here's some photos.
http://robenglish.com/Zastava_PAP_Feed_Ramp_Mod/index.htm
http://www.youtube.com/watch?v=6Y5fCOvHKzg