How often must the M120 bore be swabbed at lower elevations?

Swabbing the bore of the M120 mortar is a critical maintenance practice designed to ensure the weapon functions safely and effectively. At lower elevations, the recommendation is to swab the bore after every five rounds. This practice is important because the accumulation of residue from previous firings can lead to dangerous conditions, including the risk of misfires or reduced accuracy. By adhering to this swabbing frequency, soldiers can maintain a clear bore, ensuring that any buildup of material is removed before it can impact the performance of subsequent rounds.

In situations where firings occur frequently, such as during training exercises or live fire missions, consistent maintenance like this not only prolongs the life of the mortar but also helps to maintain the safety of the crew operating the weapon.