US Cartridge, 40mm CS, XM651, XM651E2
Cartridges XM651 and XM651E1 are CS loaded cartridges which produce a nonpersistent irritating effect. They will function against earth, gravel, brush, sandbags and bamboo; however, they are especially effective when fired into an inclosed area. These cartridges are distinguished by a flat-nosed aluminum projectile circled by two rotating bands 3/16 of an inch apart. The payload (2 oz of CS pyrotechnic mixture) is loaded into the projectile body. There is a 3/8 inch vent hole in the base of the projectile which is closed by a round plastic plug. The projectile is assembled to a cartridge case containing a percussion primer and a propelling charge. The cartridge case base is ringed with 6 equally spaced notches. Both XM651 series cartridges use PD fuze XM581E1. However, the XM651E1 is distinguished from the XM651 by the fact that it employs a modified version of the fuze. This modification (not visible to the user) consists of an indentation in the top surface of the fuze.