In a large bowl, combine pork, beef, and garlic. In another bowl, stir together salt, brown sugar, pepper, marjoram, allspice, and liquid smoke. Combine mixtures and knead with your hands until well combined.

Fill casings with meat mixture and refrigerate, 8 hours to overnight. Boil or grill before serving. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C).