Never done it myself, but I know enough to tell you most of those stories about people ripping their own eyeballs out, eating their own faces etc. is total bullshit.
If it sounds impossible it probably is, and with the amount of fat and muscle keeping your eye balls inside of your head removing them with your bear hands seems pretty impossible to me. This is of course all media hype coupled with criminals blaming their irrational behavior on drugs even when that wasn't the case.
Phencyclidine is not very common, only in certain areas like Washington DC, LA, and Philadelphia among others.
PCP users are often characterized as violent or suicidal. However, this portrait of a PCP user may not be accurate. Dr. Jaime Diaz, a professor in the Department of Psychology at the University of Washington, reviewed many of the published reports of PCP use in his book, How Drugs Influence Behavior. A Neuro-Behavioral Approach (Upper Saddle River (NJ): Prentice Hall, 1997). He states that PCP use rarely results in violence and concludes that:

"Phencyclidine does not cause aggression or criminal behavior."
http://faculty.washington.edu/chudler/pcp.html

The only substance with a known significant link to increased incidents of violent behavior is and always has been alcohol.