In a large bowl combine the steak sauce, the egg, the onion, the salt, the beef, and the breadcrumbs, mixing well. Formthe meat mixture into 6 patties. Cook the patties on a preheated barbecue grill set over medium-hot coals, turning once, for 3 to 4 minutes on each side, or until they are no longer pink in the middle. Serve the patties on the buns.