I don't see why your set-up won't be just fine. There are no telling how many turkeys that have succombed to a 2¾" 12ga loads. Would you stand and let someone shoot at you with the 2¾"? I don't think so.

Just pattern so you know your effective range well and all should be fine. Good advice from all above.

Oh, if your wife won't let you pay big bucks for a new pump or autoloader, see if she'll go ~$80 at Wal-Mart for a NEF single shot 3½" magnum.

Romans 8:28