Which type of M249 round contains no propellant or primer?

The M232 Dummy round is designed specifically for training purposes and does not contain any propellant or primer, which distinguishes it from other types of ammunition. This feature makes it safe for practice scenarios where live ammunition should not be used. Dummy rounds like the M232 are vital for drills and weapon handling training, allowing users to experience the weight and feel of the weapon without the risks associated with live rounds.

In contrast, the M200 Blank does contain a propellant charge, although it lacks a projectile, allowing for sound and recoil similar to live fire without a bullet being expelled. The M973 Short Range Training round is designed for reduced range training but still contains propellant. The M240B Ball round is a standard live round that includes both propellant and a projectile, so it does not meet the criteria of having no propellant or primer. By understanding these distinctions, one can see why the M232 Dummy is the correct answer in this context.