The M864 projectile is a dual-purpose ICM projectile that incorporates base burn technology to increase its range. The projectile is capable of delivering 24 M46 and 48 M42 dual-purpose anti-materiel/anti-personnel grenades at ranges out to 29 kilometers. Base burn technology was developed to reduce the amount of base drag on a projectile, thereby increasing the achieved range. The drag is reduced by a (base) burner unit located on the base of the projectile. Once ignited, the base burner unit bleeds hot gas which causes the flow of air at the base to be less turbulent. The decrease in turbulence causes less base drag. (Base drag accounts for about 50 percent of total drag.) The amount of thrust produced by the base burner unit is negligible and does not serve the same function as the rocket motor on RAP.
The M864 projectile is not ballistically matched to any projectile currently in the inventory, but because of the similarity of the trajectories, firing data for the M864 can be determined from the M549A1 firing data.