What is a primary function of the M62 Tracer ammunition fired from the M240?

The M62 Tracer ammunition fired from the M240 has several significant functions that contribute to its effectiveness in tactical scenarios. One of its primary functions is observation of fire. The distinctive bright trace allows shooters to visually track the bullet's trajectory, which aids in adjusting fire to improve accuracy during engagement with targets. This helps in identifying whether the rounds are falling short or over the target, allowing corrections to be made accordingly.

In addition, tracer rounds serve as a method of signaling. Shooters can use them to communicate with teammates or to indicate specific areas of interest or targets, facilitating coordination in combat situations.

While calibrating weapons is not typically a primary function of tracer ammunition, it can assist in this context during training exercises or tests by providing a visual indication of where shots are landing relative to the intended target.

Thus, given the functions of observation of fire and signaling, along with its potential role in calibration scenarios, all of these uses collectively underscore the versatility of M62 Tracer rounds in combat and training, which justifies the choice of all the listed options.