Preheat the Oven to 300 degrees. In a large skillet, cook the bacon until partially done. Add the beef and onion and cook. Stirring to break up the ground beef. Cook until the beef is browned, then drain off the fat. Add the Ketchup, Brown Sugar, Mustard, Salt, and Vinegar. Stirring to blend it all together. Spoon this mixture into the 4 Quart Casserole Baking Dish. Drain all of the beans and add them to the mixture. Stirring lightly to blend them in. Bake for 1 hour.