Final answer:
Weapons qualifications validity periods are specified in IAW 3-20.40. It's essential to consult the most recent document for an accurate timeframe as military regulations can be updated.
Step-by-step explanation:
According to IAW 3-20.40, which stands for Infantry Accuracy Weapon, weapons qualifications are valid for a specific period of time after a service member has completed their qualifications. This document governs how long the qualifications are considered valid for the purpose of military standards and readiness. However, without the exact text or current knowledge of the IAW 3-20.40, it is not possible to provide a specific number of months. Military regulations can change, and it is always important to refer to the most current version of any regulation.