THE COST OF LETHALITY: A COMPARATIVE MODEL OF PAST AND FUTURE MARINE CORPS BATTLE RIFLES

Abstract

In 2019, the Army identified a shortfall in the ability of their battle rifle, the M4, to deliver lethal effects against modern adversary body armor. To overcome the shortfall, they developed their Next Generation Squad Weapon, the XM7. In 2017, the Marine Corps equipped its infantry forces with the M27, a new rifle with the same caliber as the M4. The Marine Corps now needs to determine whether to adopt the XM7 as its battle rifle. The Marine Corps has directed a study of ballistics and load testing, as well as a combat model to be developed by the Marine Corps’ Operations Analysis Directorate. Agent-based simulation in the Map Aware Nonuniform Automata combat modeling environment is used to determine what characteristics are key for an infantry fighting rifle to maximize mission success and minimize casualties. A scenario where a meeting engagement occurs between a Marine rifle squad and an adversary squad is simulated 16,100 times while varying Marine rifle characteristics. Results indicate that it is critical that an infantry fighting rifle be able to engage targets at long ranges with high lethality. The rifle must also provide precise fires and manageable recoil to allow quicker reengagement of targets. It is recommended that the Marine Corps pursue improvements to the lethality of the round fired by the M27. If the round cannot be improved, the Marine Corps should consider the XM7, but must lighten the load of infantrymen to allow them to carry more ammunition.