Which type of round is primarily used for smoke?

The M819 round is specifically designed for creating a smoke screen on the battlefield. It is classified as a smoke round and is utilized to obscure vision and provide cover for troop movements or operations. The composition of the M819 allows it to produce a dense, effective smoke, which is crucial during offensive or defensive maneuvers.

This type of round is vital in military tactics, allowing forces to conceal their positions or aid in the retreat and regroup of units. Its effective smoke generation capabilities make it an essential tool for commanders who need to manage visibility during operations.

In contrast, the other rounds listed serve different purposes, such as high explosive or illumination, which do not fulfill the specific function of generating smoke for tactical use. Hence, the M819 stands out as the dedicated choice for creating smoke.