docshooter

Just joined this morning. I've been hunting with slug guns for years, but had the opportunity to buy a Beretta AL 2 12 ga birdgun this weekend, so I pulled the trigger. I have always wanted a Beretta semiauto, but never thought my first one would be a bird gun. It's 2 3/4 shells only, and I don't think I should put steel through it. It was made in 1973. What are the proper rounds for this gun?
Thanks for the help and Merry Christmas