What is the function of the forward assist button on an M4/AR15 rifle?
When doing an excessive amount of shooting or using dirty ammo like WOLF brand, the cartridge can get stuck maybe a half inch from being fully seated in the chamber due to excessive carbon buildup. The rifle will not fire if the cartridge is not seated and the bolt is not fully in battery. The forward assist will help you run it in firmly. If you are using the forward assist at all, you should stop and clean the weapon if at all possible. This was the cause of the very first malfunction complaints on the original GI M16 in Viet Nam. They added a forward assist to give the operator a tool to keep throwing lead under adverse conditions, but what made the true difference was to change the propellant in the cartrdidges they used, the first brands were too dirty for any useful purpose.
