And how many rounds were fired?

According to Wikipedia, about 30 rounds were fired in 30 seconds during the famous gun battle at the O.K. Corral. Here is more:

Despite its name, the gunfight actually occurred in a narrow lot six doors west of the rear entrance to the O.K. Corral on Fremont Street, and also in the street. The two opposing parties were initially only about 6 feet (1.8 m) apart. About thirty shots were fired in thirty seconds.