What type of round and fuze is generally used during the adjusting phase?

During the adjusting phase of a Call for Fire, the objective is to accurately refine the targeting of artillery to ensure that subsequent rounds will effectively land on the intended target. The use of a standard High Explosive Quick (HEQ) round is appropriate during this phase because it provides a reliable and predictable explosion that can effectively indicate the accuracy of the fire.

Using standard HEQ rounds allows for immediate assessment of the target's impact as well as adjustments to be made in terms of direction and range. The energy release from these rounds also ensures they have a significant effect, making it easier for observers to determine whether corrections are needed based on visual and tactile feedback from the impacts.

Other options such as smoke rounds and illumination rounds serve different purposes. Smoke rounds are typically used for screening or concealing movements rather than for direct target impact, and illumination rounds are utilized for lighting up the battlefield or specific areas, not for direct engagement of targets. High explosive 105mm rounds, while also explosive, are less commonly specified for adjustments compared to the more versatile standard HEQ rounds, which are designed specifically for general-purpose usage in adjusting fire and subsequent engagement.