Stir together first 4 ingredients.
Cut round bread loaf in half horizontally; scoop out bottom, leaving a 1/2-inch-thick shell.
Spoon half of olive mixture into bread shell. Layer with salami, cheese, pepperoni, and remaining olive mixture. Cover with bread top. Wrap loaf tightly with plastic wrap, and chill 8 to 24 hours. Cut loaf into wedges.