Only one. A round stuck about half way in the chamber in my Beretta 92fs. The slide couldn't be pulled back by normal hand strength. I had to carefully use a block of wood, and light hammer to tap it open, and remove the round. I couldn't see anything obvious as to why it got stuck. I cleaned the gun, which had been shot only about 30 times on that range session, and maybe 300 rounds total. I haven't had a problem since.
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!