What type of lot number is assigned to a combination of 5.56 mm ball and tracer packed together for field use?

The correct answer is that the lot number assigned to a combination of 5.56 mm ball and tracer packed together for field use is a functional lot number. This classification is utilized when different types of ammunition, which serve distinct purposes but are packaged together, need to maintain their functional characteristics. By assigning a functional lot number, it ensures that the ammo's intended application, such as for training or operational use, is preserved and easily identifiable.

This is especially important in military operations where specific types of ammunition are utilized together to achieve tactical objectives. In this context, the ball and tracer ammunition are combined in a way that enhances their operational effectiveness, thus necessitating the assignment of a lot number that reflects their combined functional use.